University of Virginia Library

2. REPRODUCTION.

Nutrition and reproduction[1] are the two great functions of life, being common, not only to all animals, but to both animals and plants, to all classes of living creatures. The object of the first is the development and maintenance of individual existence; the second has for its end the production of new individuals, or the preservation of the race. Nutrition is a purely selfish process; reproduction is purely unselfish in its object, though the human species, unlike the lower animals, which, while less intelligent, are far more true to nature, too often pervert its functions to the most grossly selfish ends. [1] "Science and the Bible," by the author, pp. 36-46.

Reproduction Common to All Living Things. — As before remarked, reproduction is a function common to all animals and to all plants. Every organized being has the power to reproduce itself, or to produce, or aid in producing, other individuals like itself. It is by means of this function that plants and animals increase or multiply.

When we consider the great diversity of characters illustrated in animal and vegetable life, and the infinite variety of conditions and circumstances under which organized creatures exist, it is not surprising that modes of reproduction should also present great diversity, both in general character and in detail. We shall find it interesting and instructive to consider some of the many different modes of reproduction, or generation, observed in different classes of living beings, previous to entering upon the specific study of reproduction in man. Before

doing this, however, let us give brief attention to a theoretical form of generation, which cannot be called reproduction, known as —

Spontaneous Generation. — By this term is meant the supposed formation of living creatures directly from dead matter without the intervention of other living organisms. The theory is, in substance, an old one. The ancients supposed that the frogs and other small reptiles so abundant in the vicinity of slimy pools and stagnant marshes, were generated spontaneously from the mud and slime in which they lived. This theory was, of course, abandoned when the natural history of reptiles became known.

For several thousand years the belief was still held that maggots found in decaying meat were produced spontaneously; but it was discovered, centuries ago, that maggots are not formed if the flesh is protected from flies, and hence must be the larvæ of a species of this insect. A relic of the ancient belief in spontaneous generation is still found in the supposition that horse-hair snakes, so-called, are really formed from the hairs of horses. This belief is quite common, but science long ago exposed its falsity. It is now known that the horse-hair snake is a parasitic worm, which spends part of its existence in the stomach of a certain species of beetle. After beginning its independent existence, it frequents moist places, such as stagnant pools by the road-side, watering troughs, etc. When the water dries up, the horse-hair snake becomes dry and apparently lifeless, and shrivels up, so that it is not readily discovered. A new rain moistens the little creature, and brings it into active life again so suddenly that it seems

like a new creation, or, according to the popular opinion, appears to be converted from a dead hair into a living snake.

Germs. — When the microscope was discovered, it revealed a whole new world of infinitesimal beings, known as germs, or bacteria, which were at first supposed to be of spontaneous origin; but careful scientific investigation has shown that even these mere specks of life are not independent of parentage. M. Pasteur and, more recently, Prof. Tyndall, with many other distinguished scientists, have demonstrated this fact beyond all reasonable chance for question.

One fact which gave rise to the belief in the spontaneous origin of germs, is their remarkable vitality. These microscopic specks of life have been known to stand a temperature of ten degrees below zero, and considerably above the boiling point of water. A sufficiently high degree of heat, however, or long-continued boiling, has been proven by M. Pasteur to be fatal to them, and by this means the doctrine of spontaneous generation was overthrown.

It is, then, an established law, that every living organism originates with some previously existing living being or beings.

It may be queried, If it be true that life is but a manifestation of the ordinary forces of matter, — which are common to both dead and living matter, — being dependent upon arrangement, then why may it not be that dead matter may, through the action of molecular laws, and without the intervention of any living existence, assume those peculiar forms of arrangement necessary to constitute life, as supposed by the advocates of the theory

in question? It is true that some who recognize the fact that life is the result of organization, maintain the doctrine of spontaneous generation; that is, the production of life without any agency other than the recognized forces of nature being brought about simply by a fortuitous combination of atoms. Although this doctrine cannot be said to be inconsistent with the theory of life presented, yet it is by no means a legitimate or necessary result of it; and observation proves its falsity.

Origin of Life. — The testimony of all nature, as almost universally admitted by scientific men, is that life originated through a creative act by the first great Cause, who gave to certain bodies the requisite arrangement or organization to enable them to perform certain functions, and delegated to them the power to transmit the same to other matter, and thus to perpetuate life. The Creator alone has the power to originate life. Man, with all his wisdom and attainments, cannot discover the secret of organization. He may become familiar with its phenomena, but he cannot unravel, further, the mystery of life. The power of organizing is possessed only by the lower class of living or organized bodies, those known as vegetable organisms, or plants. A grain of wheat, a kernel of corn, a potato, when placed under favorable conditions, takes the inert, lifeless particles of matter which lie about it in the earth and air, and organizes them into living substances like itself.

To man and animals the Creator delegated the power to form their own peculiar structures from the vitalized tissues of plants. Thus, both animal and vegetable life is preserved without the necessity of continued acts of creative power, each plant and each animal possessing

the power, not only to preserve its own life, but also to aid, at least, in the perpetuation of the species. The record of creation in Genesis harmonizes perfectly with this view, it being represented that God formed (organized or arranged) man, animals, and vegetable productions from the earth.

Simplest Form of Generation. — Deep down beneath the waters of the ocean, covering its bottom in certain localities, is found a curious slime, which, under the microscope, is seen to be composed of minute rounded masses of gelatinous matter, or protoplasm. By watching these little bodies intently for a few minutes, the observer will discover that each is a living creature, capable of moving, growing, and assuming a variety of shapes. Continued observation will reveal the fact that these little creatures multiply; and a more careful scrutiny will enable him to see how they increase. Each divides into two equal parts so nearly alike that they cannot be distinguished when apart. In this case, the process of generation is simply the production of two similar individuals from one.

Low Forms of Life. — A small quantity of slime taken from the surface of a stone near the bottom of an old well, or on the sea-side, when placed under the microscope, will sometimes be found to contain large numbers of small, round, living bodies. Careful watching will show that they also multiply by division; but before the division occurs, two cells unite to form one by a process called conjugation. Then, by the division of this cell, instead of only two cells, a large number of small cells are formed, each of which may be considered as a bud formed upon the body of the parent cell, and

then separated from it, to become by growth an individual like its parent, and, like it, to produce its kind. In this case, we have new individuals formed by the union of two individuals which are to all appearance entirely similar in every particular.

Sex. — Rising higher in the scale of being, we find that, with rare exceptions, reproduction is the result of the union of two dissimilar elements. These elements do not, in higher organisms, as in lower forms of life, constitute the individuals, but are produced by them; and being unlike, they are produced by special organs, each adapted to the formation of one kind of element. The two classes of organs usually exist in separate individuals, thus giving rise to distinctions of sex, an individual possessing organs which form one kind of element being called a male, and one possessing organs for the formation of the other kind of element, a female. The sexual differences between individuals of the same species are not, however, confined to the sexual organs. In most classes of plants and animals, other sexual differences are very marked. In some of the lower orders of animals, and in many species of plants, the male and female individuals are so much unlike that for a long time after they were well known, no sexual relation was discovered.

In some species of plants, as for example the pond scums, there is apparently no distinction of sex; and yet a union of two distinct individuals is necessary for fecundation; and there is reason to believe that these two individuals, though apparently in no way dissimilar, presenting under the microscope complete identity of appearance, are really sexually distinct, one being male and the other female.

Hermaphrodism. — An individual possessing both male and female organs of reproduction, is called an hermaphrodite. Such a combination is very rare among higher animals; but it is by no means uncommon among plants and the lower forms of animal life. The snail, the oyster, the earth-worm, the barnacle, and the common tape-worm are examples of true hermaphrodites. So-called human hermaphrodites are usually individuals in whom the sexual organs are abnormally developed, so that they resemble those of the opposite sex, though they really have but one sex, which can usually be determined with certainty. Only a very few cases have been observed in which both male and female organs were present.

There is now living in Germany an individual who bears the name of a woman; but learned physicians have decided that the person is as much man as woman, having the organs of both sexes. What is still more curious, this person has the feelings of both sexes, having loved first a man, and afterward a woman. There have been observed, also, a very few instances of individuals in whom the sexual organs of neither sex were present. It thus appears that a person may be of both sexes, or of no sex at all.

Sex in Plants. — To one unacquainted with the mysteries of plant life and growth, the idea of attaching sexuality to plants seems very extraordinary; but the botanist recognizes the fact that the distinctions of sex are as clearly maintained in the vegetable as in the animal kingdom. The sexual organs of the higher orders of plants are flowers. That part of the flower which produces seeds, answers to the female; another part, which is incapable of forming seeds, answers to the male.

The fertile and the sterile flowers are sometimes produced on separate plants. Very frequently, they are produced upon separate parts of the same plant, as in the oak, walnut, and many other forest trees, and Indian corn. In the latter plant, so familiar to every one, the "tassel" contains the male flowers, and the part known as the "silk," with the portion to which it is attached, — which becomes the ear, — the female, or fertile flowers. In a large number of species, the male and female organs are combined in a single flower, making a true hermaphrodite.

Sex in Animals. — As previously remarked, individuals of opposite sex usually differ much more than in the character of their sexual organs. Among higher animals, the male is usually larger, stronger, and of coarser structure than the female. The same contrast is observed in their mental characters. With lower animals, especially insects, the opposite is often observed. The female spider is many times larger than the male. The male ant is small in size when compared with the female. Nevertheless, in all classes of animals, the difference in the structure and the functions of the sexual organs is the chief distinguishing characteristic. These differences are not so great, however, as they might at first appear. The male and female organs of reproduction in man and other animals, which seem so dissimilar, when studied in the light shed upon this subject by the science of embryology are found to be wonderfully alike in structure, differing far more in appearance than in reality, and being little more than modifications of one general plan. Every organ to be found in the one sex has an analogue in the other which is complete in every particular, corresponding in function, in structure, and usually in position.

Other Sexual Differences. — In this country there is between five and six inches difference in hight, and about twenty pounds difference in weight, between the average man and the average woman, the average man being about five feet, eight inches in hight, and weighing one hundred and forty-five pounds; while the average woman is five feet, two or two and one-half inches in hight, and weighs one hundred and twenty-five pounds. The relation of the sexes in hight and weight varies in degree in different countries, but is never changed. The average hight and weight of American men and women is considerably above that of the average human being.

Men and Women Differ in Form. — The differences in form are so marked that it is possible for the skilled anatomist to determine the sex of a human being who has been dead for ages, by an examination of the skeleton alone. In man, the shoulders are broad, the hips narrow, and the limbs nearly straight with the body. In woman, the shoulders are narrow and usually rounded, and set farther back, the collar-bone being longer and less curved, giving the chest greater prominence; while the hips are broad.

The consequence of these differences is that woman is generally less graceful and naturally less skillful in the use of the extremities than man, and hence less fitted for athletic sports and feats requiring great dexterity. A girl throws a stone awkwardly, less from want of practice than from a natural peculiarity of physical structure., A woman walks less gracefully than a man, owing to the greater relative breadth of her hips, requiring a motion of the body together with that of the limbs. In consequence of this peculiarity, a woman is less fitted for walking long distances.

The Male and the Female Brain. — But there are other important physical differences to which we must call attention. Man possesses a larger brain than woman, but she makes up the deficiency in size by superior fineness in quality. The female brain differs from the masculine organ of mentality in other particulars so marked that one who has given the subject attention can determine with perfect ease the probable sex of the owner of almost any skull which might be presented to him. This difference in the conformation of the skull is undoubtedly due to a difference in mental character, which, in turn, depends upon a difference in cerebral development. Faculties which are generally largely developed in one, are usually smaller in the other; and the reverse.

There has been much discussion as to which sex possesses the stronger brain. The fact that the brain of the average woman weighs but forty-two ounces, while that of the average man weighs forty-nine ounces, has been stated as evidence that there is a corresponding difference in mental capacity. Those who advocate this theory seem to have lost sight of the fact that size alone is by no means a measure of power. The elephant possesses a much larger brain than the largest human brain ever weighed, and yet the intelligence of the elephant, remarkable as it is for a beast, is infinitely inferior to that of man. Quality as well as quantity must be taken into consideration, and it must be shown that the physical organization of man is finer in quality than that of woman, before the claim of superiority can be established. It is certainly reasonable to suppose that the female brain, as well as the female bones and muscles,

is of a finer texture and more delicate organization, and hence is possessed of greater intelligence than the male brain of equal size.

But the most remarkable fact of all, and one which seems to have escaped the attention of those who have written upon this subject, is that the comparison of the male and female brains has been made without regard to the relative average sizes of male and female bodies. The average man is larger than the average woman; he has larger bones, larger muscles, and in all respects a much larger development; while the average woman possesses small bones and muscles, though having a larger proportion of adipose tissue. But the average woman's brain, while smaller than that of the average man, is really larger in proportion to her body.

Thus it appears that in an argument based upon brain work irrespective of quality, woman has the advantage; and if it be granted that to this superior relative size of brain is added superior quality, the weight of argument predominates in favor of superior mental capacity in woman rather than in man.

From the author's standpoint, however, all these arguments are unnecessary. That the brain of the average woman differs in quality from the brain of the average man, is a fact too patent to require argument for its support. Each class of minds has its sphere, and is in its sphere superior. Men are undoubtedly best fitted for their sphere in life, and women for theirs; and yet it is undoubtedly true that among women there are to be found numerous exceptions, some seeming to be adapted for muscular rather than feminine pursuits, and others being vastly better fitted for some of the

vocations in life which are monopolized by men to a great extent, than are some men.

Vital Organs of Man and Woman. — The anatomist also observes an interesting difference in the size of the various vital organs. For example, while a woman has a heart proportionally smaller than the same organ in man, she has a larger liver. Thus, while less fitted for severe physical exertion by less circulatory power, she has superior excretory powers.

Woman Less Muscular, More Enduring. — This peculiarity of structure is perfectly harmonious with the fact which experience has established so often as to make the matter no longer a question, that woman is less fitted for severe muscular exertion than man, but possesses in a superior degree the quality known as endurance. With a less robust frame, a more delicately organized constitution, she will endure for months what would kill a robust man in as many weeks. More perfect elimination of the wastes of the body secures a higher grade of vitality. On no other hypothesis could we account for the marvelous endurance of the feminine part of the civilized portion of the human race, ground down under the heel of fashion for ages, "stayed," "corseted," "laced," and thereby distorted and deformed in a manner that would be fatal to almost any member of the masculine sex.

A Pathological Difference. — Nearly all physiologists mention another particular in which woman differs materially from man; viz., in naturally employing, in respiration, chiefly the upper part of the lungs, while man breathes chiefly with the lower part of the lungs. For several years, we have carefully studied this ques-

tion, and we have been unable to find any physiological or anatomical reason sufficient to account for this fact, if it be such.

Why a Woman does Not Breathe Like a Man. — It is undoubtedly true that most women do breathe almost exclusively with the upper part of the chest; but whether this is a natural peculiarity, or an acquired, unnatural, and depraved one, is a question which we are decidedly inclined to answer in harmony with the latter supposition, basing our conclusion on the following undeniable facts: —

1. In childhood, and until about the age of puberty, respiration in the boy and the girl is exactly the same.

2. Although there is a change in the mode of respiration in most females, usually soon after the period of puberty, marked by increased intercostal respiration and diminished abdominal or deep respiration, this change can be accounted for on other than physiological grounds.

3. We believe the cause of this modification of respiration is the change in dress which is usually made about that time. The young girl is now becoming a woman, and must acquire the art of lacing, wearing a corset, "stays," and sundry other contrivances which will aid in producing a "fine form," by distorting and distroying{sic} all natural grace and beauty in the "form divine."

4. We have met a number of ladies whose good fortune and good sense had delivered them from the distorting influence of corset-wearing and tight-lacing, and we have invariably observed that they are capable of as deep respiration as men, and practice it naturally.

We are thoroughly convinced that this so-called physiological difference between man and woman is really a pathological rather than a natural difference, and is due to the evils of fashionable dress, which we have exposed at some length in another work exclusively devoted to that subject.[2] In short, we believe that the only reason why women do not, under ordinary circumstances, breathe as do men, is simply because they cannot breathe naturally. [2] "Evils of Fashionable Dress, and How to Dress Healthfully."

The Reproductive Elements. — As has been previously observed, in all except the very lowest forms of life, two elements are necessary to the production of a new individual, or a reproduction of the species, — a male element and a female element. The special organs by means of which these elements are produced, brought together, and developed into the new individual in a more or less perfect state, are termed sexual organs. As an introduction to the specific study of the sexual organs in the human species, let us briefly consider the —

Sexual Organs of Plants. — Flowers are the sexual organs of plants. Nothing is more interesting in the natural world than the wonderful beauty, diversity, and perfect adaptability to various conditions and functions, which we see in the sexual parts of plants. An exceedingly interesting line of study, which has occupied the attention of many naturalists, is the wonderful perfection displayed in the adaptability of the male and female parts of plants to each other. Without burdening the reader with unnecessary technicalities of detail, we will briefly notice the principal parts of vegetable sexual organs as illustrated in flowers.

Complete flowers are made up of four parts, two of which, the stamen and pistil, are essential, while the other two, the calyx and corolla, are accessory.

The calyx is that part which surrounds the flower at its outer and lower part. It varies greatly in form and color, but is most frequently of a green or greenish color.

Just within the calyx is the corolla, which usually forms the most attractive, showy, and beautiful part of the flower. The beautifully colored petals of the rose, geranium, dahlia, and other similiar{sic} flowers, form their corollas.

Vegetable Husbands. — Within the cup formed by the calyx and corollas are placed the stamen and pistils of the flower, the first being the male organs proper and the second the female organs of the flower

The stamen is composed of a stem, or filament, at the summit of which are placed two little sacs, called the anther, containing a fine, microscopic dust, the pollen, which contains the male reproductive element of the flower. This part of the plant corresponds to the male organ of reproduction in animals. A stamen has been called, not inaptly, a vegetable husband. Some flowers have many stamens, or vegetable husbands, which reminds us of the custom in Thibet and some other Eastern countries which allows a woman to have several husbands.

Polygamous Flowers. — The great naturalist, Linnæus, whose name was immortalized by his careful study and classification of organized life, made the number of stamens possessed by various flowers the basis of a systematic classification.

For example, a flower having but one stamen was classed as monandria which means, literally, one husband; one having two stamens was classified as diandria; flowers having a large number of male organs were termed polyandria, or many husbands.

The Female Organs of Flowers. — The pistil occupies the very center of the flower. It produces and contains in a cell, the female element, termed the ovule. It is surmounted by the style and the stigma.

A series of plants in which the sexual organs are not visible to the eye are called cryptogamia, which means, literally, hidden marriages.

As we proceed to study the anatomy of the human sexual apparatus, we shall be constantly struck with the remarkable correspondence between animals and vegetables in the structure and functions of the sexual apparatus.

Sexual Organs of Animals. — The male reproductive element is called spermatozoon, or zoosperm. The female element is called an ovum, literally, an egg.

The Spermatozoon. — The male reproductive element of animals is formed by an organ called the testis, or testicle, of which each male possesses two. They are elastic, glandular bodies, and are formed within the cavity of the abdomen, near the kidneys, but usually pass out of the abdominal cavity, and descend to their permanent position before birth. The opening in the abdominal wall is usually completely closed in a short time; but occasionally it remains open, giving rise to congenital hernia, an accident in which a loop of intestine follows the testicle down into the scrotum, either completely or partially. In a few animals, as in the por-

cupine, the opening is never fully closed, and the testis remains in the cavity of the body most of the time, passing out only at certain periods. We also occasionally meet cases of human beings in which the testes have never descended from their place in the abdominal cavity, giving the individuals the appearance of eunuchs.

When the testicles are thus retained, they are usually imperfectly developed, and consequently the person is likely to be sterile. This is not always the case, however, and hence it occurs that men who apparently have no testicles, become the fathers of children.

In the whale, the elephant, and the seal, the testicles remain permanently within the abdominal cavity, though in most animals they are supported outside the body in a sac, as in man.

The left testicle is sometimes a little smaller than the right, and commonly hangs a little lower. The testicles are connected with the urinary passage by means of two ducts, which terminate near the base of the bladder.

Spermatozoa. — A single spermatozoon somewhat resembles a tadpole in appearance, having, however, a much longer tail in proportion to the size of the body.

Human spermatozoa are about 1/1600 of an inch in length. Those of reptiles are very much larger. One of the remarkable features of these minute elements is their peculiar movements. While alive, the filamentous tail is in constant action in a manner strongly resembling the movements of the caudal appendage of a tadpole. This wonderful property led the earlier observers to believe that they were true animalcula. But they are not to be regarded as such, though one can scarcely

make himself believe otherwise while watching their lively evolutions, and apparently volitionary movements from one point to another.

Spermatozoa originate in the testis as cells, which are filled with granules. After a time, each granule acquires a long appendage, and then the cell has become converted into a bundle of small zoosperms. Development still continues, until finally the thin pellicle on the outside of the bundle is ruptured, thus liberating the spermatozoa, which speedily complete their full development. The spermatozoon is pure protoplasm, which is the basis of all life, and its power of spontaneous motion is due to this fact.

In man, the formation of spermatozoa continues with greater or less rapidity from puberty to old age, though at the two extremes of existence they are imperfectly developed. When not discharged from the body, they are said to be absorbed. Some physiologists claim that they are composed of a substance identical with nerve tissue, and that by absorption they play a very important part in the development and maintenance of the nervous system.

It is asserted by good authorities that the reproductive element in man is not sufficiently developed to be really fit for the reproduction of the species before the age of twenty-four or twenty-five. After the age of forty-five or fifty, this element deteriorates in quality, and is again unfitted for vigorous procreation.

The fully developed zoosperms are suspended in a transparent, gelatinous fluid, which, mingled with the secretion of the prostate gland and other fluids which it meets during its expulsion from the body, constitutes the semen.

The Ovum. — The female element of generation, the ovum, is produced by an organ called the ovary, of which there are two in each individual. In size and form, the ovary closely resembles the testicle. Like the latter organ, also, it is formed within the body early in the process of development; but instead of passing outward and downward, as does the testicle, it remains within the abdominal cavity, suspended in place by ligaments. It is connected with a duct, which receives the ovum as it is discharged, and conveys it to the uterus.

The human ovum varies in size from 1/1240 to 1/1120 of an inch in diameter, and consists of a single cell.

Ovulation. — Ova are not formed in such large numbers as zoosperms. As a general rule, in the human female, a single ovum is developed and discharged once in about four weeks, during the period of sexual activity. This view is disputed by some physiologists, who claim that ovules are constantly being formed and thrown off, not only during that period of a woman's life during which child-bearing occurs, but prior and subsequent to the child-bearing period. The development of the ovaries is symmetrical in all the higher classes of animals, with the exception of birds, in whom the right ovary is usually atrophied or undeveloped, allowing room for the egg produced by this class of the animal kingdom.

Fecundation. — It is often asked, and the question has elicited some discussion, Which is the principal reproductive element, the zoosperm, or the ovum? The ancients supposed the male element to be the essential element, being simply nourished and developed by the female; but modern research in biological science does not sustain this view. Probably neither one enjoys

special pre-eminence; for neither can undergo complete development without the other. In very rare cases, the ovum has been observed to undergo a certain amount of development of itself; but a perfect individual can be produced only by the union of the two kinds of elements, — a process known as fecundation.

The fact that the spermatozoa are swallowed up and lost in the ovule, would rather indicate that the spermatozoa are inferior in physiological importance to the ovule, and that their chief action is to stimulate the ovule to active growth and complete development.

The instant the union between the ovum and spermatozoa occurs, the life of a new individual begins. All the changes which result between that moment and the birth of the individual, are those of development only. Indeed, the same existence continues from the instant of the union of the two elements, not only until birth, but through growth, the attainment of maturity, the decline of life, and even until death.

It is interesting to observe the different methods by which fecundation is effected, in both plants and animals; for this is a process common to both.

Fecundation in Flowers. — The great naturalist, Linnæus, was the first to explain the reproductive process in plants. He tells us that "the flower forms the theater of their amours; the calyx is to be considered as the nuptial bed; the corolla constitutes the curtains; the anthers are the testes; the pollen, the fecundating fluid; the stigma of the pistil, the external genital aperture; the style, the vagina, or the conductor of the prolific seed; the ovary of the plant, the womb; the reciprocal action of the stamens on the pistil, the accessory process of fecundation."

Thus marvelous is the analogy between the reproductive organs and their functions in plants and animals. Through this one vital process we may trace a close relation between all the forms of life, from the humblest plant, or even the mere specks of life which form the green scum upon a stagnant pool, to man, the masterpiece of creation, the highest of all animate creatures. In all the realm of nature there can be found no more remarkable evidence of the infinite skill and wisdom of the Creator of all things.

In many instances, the action of plants seems almost to be prompted by intelligence. At the proper moment, the corolla contracts in such a way as to bring the stamens nearer to the stigma, or in contact with it, so as to insure fecundation. In some aquatic plants, the flowers elevate themselves above the surface of the water while the process of fecundation is effected, submerging themselves again immediately afterward.

Other very curious changes occur in flowers of different species during the reproductive act. The stigma is observed to become moistened, and even to become distinctly odorous. Often, too, it becomes intensely congested with the juices of the plant, and sometimes even acquires an uncommon and most remarkable degree of contractility. This is the case with the stigma of the tulip and one variety of sensitive plant, and in these plants it is observed to occur not only after the application of the pollen to the stigma, but when excited by any other means of stimulation. The flowers of some plants, during and after fecundation, also show an increase of heat, in some cases so marked as to be readily detected with the thermometer. This is said to be especially the case with the arum of Italy.

In some plants in which the pistil is longer than the stamens, thus elevating the stigma above the anthers, the female organ is often observed to bend over and depress itself so as to come within reach of the anthers.

In most instances, the fecundation of flowers is chiefly effected through a purely mechanical process, though in these cases, also, we see a wonderful adaptation of parts to conditions.

Natural Adaptations. — When the male and female parts of flowers are situated on different plants, as in the case of the willow, the poplar, the melon vine, and many other species, the pollen of the male flower is wafted by the wind or a gentle breeze to the stigma of the female flower, which will usually be found at no very great distance, although fertilization may take place in this way at very considerable distances. Bees, moths, and many other species of insects, serve a very important purpose in this work, transporting the fertilizing dust upon their wings, antennæ, sucking tubes, and feet. Small birds, and even the humble snail, which would scarcely be credited with any useful function, are also very serviceable in the same direction. The part performed by insects in the reproductive process of many plants is so great that they have been very poetically termed "the marriage priests of flowers."

Nature provides for thorough fecundation in these cases, by placing the plants which bear the male and the female flowers near each other. This fact accounts for the unproductiveness of certain varieties of strawberries unless mixed with plants of some other variety, it being well known to nursery-men that some varieties produce the female parts of flowers almost exclusively.

Curious Modes of Fecundation in Animals. — The nodes by which fecundation is effected in animals are still more various and wonderful than in plants. In some of the lower animals, as in most fish and reptiles, both elements are discharged from the bodies of the parents before coming in contact, there being no contact of the two individuals. In this class of animals the process is almost wholly analogous to fecundation in those plants in which the male and female flowers are on different plants or on different parts of the same plant. In the female fish, a larger number of ova are developed at a certain season of the year, known as the spawning season. Sometimes the number reaches many thousands. At the same time, the testicles of the male fish, which are contained within the abdominal cavity, become distended with developed zoosperms. When the female seeks a place to deposit her eggs, the male closely follows; and as she drops them upon the gravelly bottom, he discharges upon them the zoosperms, by which they are fecundated. According to the testimony of an eye-witness, the waters of the North Sea are in some places turbid with the eggs of cod-fish during the spawning season.

The process is analogous in some species of frogs. When the female is about to deposit her eggs, the male mounts upon her back, and rides about until the eggs are all deposited, discharging upon them the fertilizing spermatozoa as they are laid by the female.

The male frog is enabled to maintain its hold during the long period occupied by the female in laying eggs, by means of an extra development upon the first toe of each fore-foot, which occurs at this period. At

the end of the breeding season, these temporary thumbs, being no longer needed, disappear.

In some species in which internal impregnation occurs, there is no contact between the species, but by some means not yet understood, the spermatozoa discharged by the male find their way into the internal passages of the female, where the ovules are impregnated.

In serpents, fecundation occurs by mere contact of the sexual organs. In snails, which have already been mentioned as hermaphrodite animals, each individual possessing in a perfectly developed state both male and female organs, internal fecundation occurs after a very curious fashion, thus described by the eminent naturalist, Prof. T. R. Jones, F. R. S., of London: —

"The manner in which they copulate is not a little curious, their union being accompanied by preparatory blandishments of a very extraordinary kind, that to a spectator would seem rather like a combat between mortal foes than the tender advances of two lovers. After sundry caresses between the two parties, during which they exhibit an animation quite foreign to them at other times, one of the snails unfolds from the right side of its neck, where the generative orifice is situated, a wide sacculus, which, by becoming everted, displays a sharp dagger-like spiculum, or dart, attached to its walls. Having bared this singular weapon, it endeavors, if possible, to strike it into some exposed part of the body of its paramour, who, on the other hand, uses every precaution to avoid the blow, by speedily retreating into its shell. But, at length, having received the love-inspiring wound, the smitten snail prepares to

retaliate, and in turn uses every effort to puncture its assailant in a similar manner. The darts are generally broken off in this encounter, and either fall to the ground, or remain fixed in the wounds which they have inflicted. After these preparatory stimulations, the snails proceed to more effective advances. The sac of the dart is withdrawn into the body, and another sacculus is by a like process protruded from the common generative aperture. Upon the last-named organ, two orifices are seen, one of which leads to the female generative system, while from the other a long and whip-like penis is slowly unfolded, being gradually everted like the finger of a glove, until it attains the length of an inch or more. Then each of the two snails impregnates its partner, and is itself impregnated at the same time."

In the oyster, another hermaphrodite, self-fecundation occurs. In the argonaut, a species of cuttle-fish, fecundation is effected in a most extraordinary manner. The male, which is smaller than the female, has upon the left side of its body a little sac, in which grows a coiled-up worm-like arm covered with suckers. This arm is really a sac, which communicates with the testes, and contains spermatozoa. On reaching full development, and becoming filled with spermatozoa, this curious arm detaches itself from the body of the argonaut, and begins an independent life. Floating through the water, it by and by finds a female argonaut, with which it connects itself, and impregnates it with the spermatozoa transported from the male.

In the tape-worm, a parasitic creature which is found in the human digestive canal, a very curious form of fecundation has been noted. When liberated from

the egg, it consists simply of a head with hooks, by which it attaches itself to the mucous membrane of the intestines. From the head grows out a body, which shortly divides into segments, which gradually increase in number and size. Each section contains both male and female sexual organs, and is self-fecundating. After a time, the older segments become detached, and lead independent lives, until all the ovules they contain have been deposited. It has been established that more than twenty thousand eggs are produced by a single worm.

In higher orders of animals, fecundation takes place within the generative passages of the female by contact between the male and female organs. To effect this, there are necessitated certain accessory organs, the penis in the male and the vagina in the female.

Nothing in all the range of nature is more remarkable than the adaptation of the two varieties of sexual organs in each species. This necessary provision is both a powerful means of securing the perpetuation of the species, and an almost impassible barrier against amalgamation.

The act of union, or sexual congress, is called coitus, or copulation. It is accompanied by a peculiar nervous spasm, due to the excitement of special nerves principally located in the penis in the male, and in the clitoris and vagina in the female. The nervous action referred to is more exhausting to the system than any other to which it is subject.

Union of the Ovum and Zoosperm. — The zoosperms not only come in contact with the ovum, but penetrate the thin membrane which incloses its contents, and enter its interior, where they disappear, becoming united

with its substance. In the ova of certain fishes, small openings have been observed, through which the spermatozoa find entrance. Whether such openings exist in human ova, is an undecided question; but it is probable that they do.

Curious Modes of Reproduction. — A peculiar kind of reproduction is observed in a variety of polyp, a curious animal which very much resembles a flower in appearance. It attaches itself to some solid object, and then, as it grows, sends out little protuberances resembling buds. Some of these separate and fall off, swimming about as separate animals. These never become like the parent polyp; but they lay eggs, which hatch, and become stationary polypi like their grandparent, and in their turn throw off buds to form swimming polypi. In this case we have two kinds of generation combined, alternating with each other.

Parthenogenesis. — Plant-lice afford a curious illustration of a similar generation, known as parthenogenesis. Males and females unite, and produce eggs. The creatures produced by the hatching of eggs are neither males nor perfect females. They are imperfect females. They are all alike, so that no sexual union occurs. Instead of laying eggs, they produce live young like themselves, which appear to be developed from internal buds similar to the external buds of the polyp. After this method of reproduction has continued for nine generations, a few perfect individuals appear, and the first process is repeated. While this budding process has been going on, the original insect has continued laying; and so great is the rapidity of this form of reproduction that it has been estimated that even at the end of the fifth generation, a

single insect may be the great great grandmother of nearly six billion young ones.

The common honey-bee affords another illustration like the last. A virgin queen sometimes lays eggs, which always produce males, or drones. After union with a male, she lays eggs in the royal cells, and these become perfect females like herself. She also seems to have the power to lay, at will, unfecundated eggs, from which drones are produced.

An analogous mode of reproduction prevails among certain species of worms, which multiply by simple division of the body, one portion producing the head, and the other the tail. The individuals thus produced have no sex, and may be called neuters. They go on and on reproducing in this way for several generations, until finally a new individual is produced which is sexually complete and reproduction by means of eggs is again begun.

Human Beings are Developed Buds. — It has been very aptly suggested by an eminent physiologist that the ovum and zoosperm may be correctly considered as internal buds. Thus it would appear that generation is universally a process of budding. A child is but a compound bud, an offshoot from its parents. This idea is not a mere fancy, but has a scientific basis. As all the exquisite details of the most beautiful flower are in essence contained within the tiny bud which first makes its appearance, so is the developed human being, the full-grown man or woman, virtually contained within the tiny cell called the ovum after it has been impregnated or fecundated by the zoosperms. In short, men and women are blossoms in a strictly scientific sense.

The process of fecundation in hermaphrodite animals is very peculiar. In some cases, as in the snail, the union of two individuals is usually necessary, though each possesses both kinds of organs. In other cases, as in the tape-worm, the oyster, and numerous other mollusks, a single individual has the power to fertilize its own ova, thus being wholly independent. Human hermaphrodites are usually so deformed that fecundation is not effected, which is a fortunate safeguard against the multiplication of such monstrosities.

Complemental Males. — One species of barnacle was for some time quite a puzzle to the zoologist, as no male of the species could be found, hence no means by which the eggs produced by the egg-bearing, or female, animal could be fecundated. At last, Prof. Darwin discovered, snugly hidden away in the corner of a little pocket in the female, the male animal, so unlike the female that it had never been suspected as having any relationship; but it proved, on examination by dissection, to be a fully developed male. In some varieties of this queer species, the female has been observed carrying in this little pocket two or three of these diminutive males.

Development. — After the union of the two elements, known as fecundation, or conception, if the conditions are favorable, development occurs; and the little germ is in due process of time developed into an individual which is an exact counterpart of its parents. During this developmental process, the embryonic being is variously treated by different classes of animals.

Unprotected Development. — Most fishes and reptiles discharge their ova before fecundation, or soon after, and pay no further attention to them. The fish deposits its

eggs in a little hollow scooped out in the gravelly bed of a stream, or sows them broadcast upon the waters. The turtle buries its eggs in the sand, and leaves them to be hatched by the sun. The ostrich disposes of her eggs in the same way. Many other species of animals pay no regard to the protection of the germs which are destined, if placed under favorable conditions, to become individuals like themselves.

Partial Protection of the Ovum. — There are some exceptions, however, to this general rule among fishes and reptiles. Even fishes manifest a degree of parental solicitude in certain cases. The male of a species of South American fish gathers up the eggs after fecundation has taken place, and carries them in his mouth until they are hatched. Another male fish carries the eggs of his mate in a little pouch upon the lower and posterior part of his body.

Certain species of frogs carry their eggs wound about their legs; others suspend them from the abdomen. Another variety carries its young upon its back. Prof. Wyman describes a "swamp toad" which patiently takes the eggs of his mate, one by one, and fastens them upon her back, observing great regularity in arrangement. These several devices are evidently for the purpose of protecting, in some degree, the young individuals during the helpless stage of their existence.

The eggs of sharks, which are few in number, are each provided with a horny covering and four filamentous attachments resembling the tendrils of a grape-vine, by which they become entangled among the sea-weeds, sad are thus protected.

The cuttle-fish covers its eggs between the folds of its queerly shaped body.

Some species of fish gather their eggs together in masses, and surround them by a protective covering. A species of worm carries a whole colony of little ones upon its back. Even the star-fish protects its eggs with its arms; and if they become scattered, gathers them up.

Development in the Higher Animals and Man. — Higher animals are less prolific, and their development is a more complicated process, hence, their young need greater protection; and for this reason, the ova, instead of being discharged from the body of the female after fecundation, are retained.

Curious examples of internal development sometimes occur in animals which usually deposit eggs. Snakes have been known to produce both eggs and living young at the same time. At the annual meeting of the American Society for the Advancement of Science, at Detroit, Mich., in August, 1875, we had the pleasure of examining a specimen, exhibited by Prof. Wilder, of a chick which had undergone a considerable degree of development within the ovary of the hen. It had a head, a rudimentary brain, and internal viscera, but no feathers nor limbs. It was, in fact, an egg hatched before it had been laid. The anomaly excited much interest at that time, and since, among biologists.

As we have seen that a suitable receptacle is sometimes provided outside of the body, so now a receptacle is needed, and is provided in the interior of the body of the female. This receptacle is called —

The Uterus. — This is a hollow, pear-shaped organ, located in the median line, just behind the bladder, between it and the rectum. It is supported in place

by various ligaments, and by the juxtaposition of other organs. Its larger end is directed upward, and communicates upon each side with a very narrow tube, which is prolonged outward on either side until it nearly touches the ovary of the same side. Its lower and smaller end fills the internal extremity of the passage previously described as the vagina. When the ovum is matured, it escapes from the ovary into the narrow tube referred to, called the Fallopian tube, and passes down into the cavity of the uterus. If fecundation does not occur, it is expelled or absorbed after six to twelve or fourteen days. If copulation occurs, however, zoosperms are brought into the cavity of the uterus, and, coming in contact with the ovum, fecundate it. This is conception. When the natural process is allowed to proceed, development occurs.

Gestation, or Pregnancy. — This is the term applied to the process last referred to. We shall not attempt to describe in detail this most wonderful and intricate of all living processes; but will sketch only the chief points, leaving the reader who would obtain a more complete knowledge of the subject, to consult any one of the numerous physiological and obstetrical works which deal with it in a very exhaustive manner.

As soon as the ovum is impregnated by the male element, it begins a process of symmetrical division. The first division produces two cells out of the single one which first existed. By the next division, four segments are produced; then eight, sixteen, etc. While this process is going on, the ovum becomes adherent to the internal wall of the uterus, and is soon enveloped by its mucous membrane, which grows up about it and incloses it.

The Primitive Trace. — When the process of segmentation has advanced to a certain point, the cells are aggregated together in a compact layer at the surface. Soon a straight line appears upon this layer, which is called the primitive trace. This delicate line becomes the basis for the spinal column; and upon and about it the whole individual is developed by an intricate process of folding, dividing, and reduplication of the layer of cells. One end of the line becomes the head, and the other becomes the tail. Even man has a caudal appendage at an early stage of his existence. After a further lapse of time, little excrescences, buds, or "pads" appear in the proper positions to represent the arms and legs. After further development, the ends split up into fingers and toes, and by the continued development of the parts, perfect arms and legs are formed.

Curious Relation to Lower Animals. — It is a very remarkable fact that in the lower animals we have numerous examples in which the permanent condition of the individual is the same as some one of the stages through which man passes in the process of development. The same author previously quoted makes the following interesting statements: —

"The webbed feet of the seal and ornithorhynchus typify the period when the hands and feet of the human embryo are as yet only partly subdivided into fingers and toes. Indeed, it is not uncommon for the `web' to persist to some extent between the toes of adults; and occasionally children are born with two or more fingers or toes united to their tips.

"With the seal and the walrus, the limbs are pro-

truded but little beyond the wrist and ankle. With the ordinary quadrupeds, the knee and elbow are visible. The cats, the lemurs, and the monkeys form a series in which the limbs are successively freed from the trunk, and in the highest apes they are capable of nearly the same movements as the human arm and leg, which, in their development, passed through all these stages."

Simplicity of Early Structures. — The first structures formed are exceedingly simple in form. It is only by slow degrees that the great complicity which characterizes many organs is finally attained. For example, the heart is at first only a straight tube. By enlargement and the formation of longitudinal and transverse partitions, the fully developed organ is finally produced. The stomach and intestines are also at first but a simple straight tube. The stomach and large intestine are formed by dilatation; and by growth of the tube in length while the ends are confined, the small intestines are formed. The other internal organs are successively developed by similar processes.

The Stages of Growth. — At first, insignificant in size, a simple cell, the embryonic human being steadily increases in size, gradually approximating more and more closely to the human form, until, at the end of about nine calendar months, or ten lunar months, the new individual is prepared to enter the world, and begin a more independent course of life. The following condensation of a summary quoted by Dr. Austin Flint, Jr., will give an idea of the size of the developing being at different periods, and the rate of progress: —

At the end of the third week, the embryon is a little less than one-fourth of an inch in length.

At the end of the seventh week, it is three fourths of an inch long. The liver, lungs, and other internal organs are partially formed.

At the eighth week, it is about one inch in length. It begins to look some like a human being, but it is impossible to determine the sex.

At the third month, the embryon has attained the length of from two to two and one-half inches. Its weight is about one ounce.

At the end of the fourth month, the embryon is called a fetus. It is from four to five inches long, and weighs five ounces.

At the fifth month, the fetus is nearly a foot long, and weighs about half a pound.

At the sixth month, the average length of the fetus is about thirteen inches, and its weight one and a half to two pounds. If born, life could continue a few minutes.

At the seventh month, the fetus is from fourteen to fifteen inches long, and weighs from two to three pounds. It is now viable (may live if born).

At the eighth month, the length of the fetus is from fifteen to sixteen inches, and its weight from three to four pounds.

At the ninth month, the fetus is about seventeen inches long, and weighs from five to six pounds.

At birth, the infant weighs a little more than seven pounds, the usual range being from four to ten pounds, though these limits are sometimes exceeded.

Duration of Gestation. — The length of time required for the development of a human being is usually reckoned as about forty weeks. A more precise statement places it at about two hundred and seventy-eight days. This

limit is often varied from. Cases have occurred in which a much longer time has been required; and numberless cases are recorded in which human beings have been born several weeks before the expiration of the usual time, as stated. There is some uncertainty respecting the exact length of the period of gestation, which grows out of the difficulty of determining, in many cases, the exact time when conception took place.

In the kangaroo, though the period required for development is about the same as in the human female, uterine gestation continues for only thirty-nine days. At the end of this time, the infant kangaroo is transferred to a pouch provided under the hinder part of the body of the mother, which also contains the mammary glands. To the nipple of one of these the lips of the young animal become attached, and by a curious rhythmical action of certain muscles, the paternal nourishment is regularly forced into the mouth of the little one. The eminent Prof. Owen thus remarks concerning this remarkable mode of caring for the young: —

"Thus aided and protected by modifications of structure, both in the system of the mother and in its own, designed with special reference to each others' peculiar condition, and affording, therefore, the most irrefragible evidence of creative foresight, the feeble offspring continues to increase from sustenance derived exclusively from the mother, for a period of about eight months. The young kangaroo may then frequently be seen to protrude its head from the mouth of the pouch, and to crop the grass at the same time the mother is browsing. Having thus acquired additional strength, it quits the pouch, and hops at first with a feeble and vacillating

gait, but continues to return to the pouch for occasional shelter and supplies of food, until it has attained the weight of ten pounds. After this, it will occasionally insert its head for the purpose of sucking, notwithstanding another fetus may have been deposited in the pouch; for the latter attaches itself to a different nipple from the one which has previously been in use."

Uterine Life. — The uterine life of the new individual begins with the impregnation of the ovum, which occurs the instant it is brought in contact with the zoosperms of the male. While in the uterus, the young life is supported wholly by the mother. She is obliged to provide not only for her own sustenance, but for the maintenance of her child. And she must not only eat for it, but breathe for it as well, since it requires a constant and adequate supply of oxygen before birth as much as afterward.

How the Unborn Infant Breathes. — Oxygen and nutriment are both supplied to it through the medium of an organ called the placenta, which is a spongy growth, composed almost entirely of blood-vessels, and is developed upon the inner wall of the uterus, at the point where the ovum attaches itself after fecundation. The growing fetus is connected with this vascular organ by means of a sort of cable, called the umbilical cord. The cord is almost entirely composed of blood-vessels, which convey the blood of the fetus to the placenta, and return it again. The fetal blood does not mix with that of the mother, but receives oxygen and nourishment from it by absorption through the thin walls which alone separate it from the mother's blood.

The umbilical cord contains no nerves, as there is no

nervous connection between the mother and the child. The only way in which the child can be influenced by the mother is through the medium of the blood, to changes in which it is very susceptible, as we shall see more clearly hereafter.

The cord is attached to the body of the child at the point called the navel, being cut off at birth by the accoucher. With the placenta, it is expelled soon after the birth of the child, and constitutes the shapeless mass familiarly known as the after-birth, by the retention of which the most serious trouble is occasionally caused.

Parturition, or Childbirth. — At the end of the period of development, the young being is forcibly expelled from the laboratory of nature in which it has been formed. In other words, it is born; and this process is termed parturition. Though at first thought such an act would seem an utter impossibility, yet it is a very admirable illustration of nature's adaptation of means to ends. During the months of gestation, while the uterus has been enlarging to accommodate its daily increasing contents, the generative passages have also been increasing in size, and becoming soft and distensible, so that a seeming impossibility is in due time accomplished without physical damage, though possibly not without intense suffering. However, it is a most gratifying fact that modern medical science may do much to mitigate the pains of childbirth. It is possible, by a proper course of preparation for the expected event, to greatly lessen the suffering usually undergone; and some ladies assert that they have thus avoided real pain altogether. Although the curse pronounced upon the feminine part of the race, in consequence of the sin of Eve, implies suffer-

ing in the parturient act, yet there is no doubt that the greater share of the daughters of Eve are, through the perverting and degenerating influences of wrong habits, and especially of modern civilization, compelled to suffer many times more than their maternal ancestor. We have sufficient evidence of this in the fact that among barbarian women, who are generally less perverted physically than civilized women, childbirth is regarded with very little apprehension, since it occasions little pain or inconvenience. The same is true of many women among the lower laboring classes. In short, while it is true that more or less suffering must always accompany the parturient act, yet the excessive pain usually attendant upon the process is the result of causes which can in many cases be removed by proper management beforehand and at the time of confinement.

After being relieved of its contents, the uterus and other organs rapidly return to nearly their original size.

Changes in the Child at Birth. — In the system of the child a wonderful change occurs at the moment of its expulsion into the outer world. For the first time, its lungs are filled with air. For the first time, they receive the full tide of blood. The whole course of the circulation is changed, and an entirely new process begins. It is surprising in how short a space of time changes so marvelous can be wrought.

Nursing. — The process of development is not fully complete at birth. The young life is not yet prepared to support itself; hence, still further provision is necessary for it. It requires prepared food suited to its condition. This is provided by the mammæ, or breasts, of the female, which are glands for secreting milk. The

fully developed gland is peculiar to the female; but a few instances have been known in which it has been sufficiently developed to become functionally active in men, as well as in young girls, though it is usually inactive even in women until near the close of gestation. It is a curious fact that the breasts of a new-born child occasionally contain milk.

The first product of the mammæ is not the proper milk secretion, but is a yellowish fluid, called colostrum. The true milk secretion begins two or three days after delivery.

The lacteal secretion is influenced in a very remarkable manner by the mental conditions of the mother. By sudden emotions of grief or anger, it has been known to undergo such changes as to produce in the child a fit of indigestion, vomiting, diarrhea, and even convulsions and death. Any medicine taken by the mother finds its way into the milk, and often affects the delicate system of the infant more than herself. This fact should be a warning to those nursing mothers who use stimulants. Cases are not uncommon in which delicate infants are kept in a state of intoxication for weeks by the use of alcoholic drinks by the mother. The popular notion that lager-beer, ale, wine, or alcohol in any other form, is in any degree necessary or beneficial to a nursing woman, is a great error, which cannot be too often noticed and condemned. Not only is the mother injured instead of being benefited by such a practice, but great injury, sometimes life-long in its consequence, is inflicted upon the babe at the breast, who takes the intoxicating poison second hand, and is influenced in a fourfold degree because of its feebleness and great susceptibility.