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characters that the chimpanzee's or orang's brain can be structurally distinguished from man's.

The facts of anatomy, at least, are all against us. Struggle as we may, be as snobbish as we will, we cannot shake off these poor relations of ours. Our adult anatomy at once betrays our ancestry, if we attempt to deny it. Read the first chapter of that remarkable book by Professor Drummond on the "Ascent of Man," the chapter on the ascent of the body, and the second chapter on the scaffolding left in the body. The tips of our ears and our rudimentary ear muscles, the hair on hand and arm, and the little plica semilunaris, or rudimentary third eyelid in the inner angle of our eyes, the vermiform appendage of the intestine, the coracoid process on our shoulder-blades, the atlas vertebra of our necks-to say nothing of the coccyx at the other end of the backbone-many malformations, and a host of minor characteristics all refute our denial. If we appeal from adult anatomy to embryology the case becomes all the worse for us. Our ear is lodged in the gill-slit of a fish, our jaws are branchial arches, our hyoid bone the rudiment of this system of bones supporting the gills. Our circulation begins as a veritable fish circulation; our earliest skeleton is a notochord; Meckel's cartilage, from which our lower jaw and the bones of our middle ear develop, is a whole genealogical tree of disagreeable ancestors. Our glandula thyreoidea has, according to good authorities, an origin so slimy that it should never be mentioned in polite society. The origin of our kidneys appears decidedly vermian. Time fails me to read merely the name of the witnesses which could be summoned from our own bodies to witness against us.

Even if the testimony of some of these witnesses is not as strong as many think, and we have misunderstood several of them, they are too numerous and their stories hang too well together not to impress an intelligent and impartial jury. But what if it is all true? What if, as some think, our millionth cousin, the tiger or cat, is anatomically a better mammal than I? His teeth and claws and magnificent muscles are of small value compared with man's mental power.

What a comedy that man should work so hard to prove that his chief glory is his opposable thumb, or a few ounces of brain matter! Man's glory is his mind and will, his reason and moral powers, his vision of, and communion with, God. And supposing it be true, as I believe it is true, that the animal has the germ of these also, does that cloud my mind or obscure my vision or weaken my action? It bids me only strive the harder to be worthy of the noble ancestors who have raised me to my higher level and on whose buried shoulders I stand. Whatever may have been our origin, whoever our ancestors, we are men. Then let us play the man. If we will but play our part as well as our old ancestors played theirs, if we will but walk and act according to our light one-half as heroically and well as they groped in the darkness, we need not worry about the future. That will be assured.

Says Professor Huxley: "Man now stands as on a mountain-top far above the level of his humble fellows, and transfigured from his grosser nature by reflecting here and there a ray from the infinite source of truth. And thoughtful man, once escaped from the blinding influences of traditional prejudice, will find in the lowly stock whence man has sprung the best evidence of the

splendor of his capacities, and will discern in his long progress through the past a reasonable ground of faith in his attainment of a nobler future."

We have sketched hastily and in rude outline the anatomical structure of the successive stages of man's ancestry; let us now, in a very brief recapitulation, condense this chronicle into a historical record of progress.

We began with the amoeba. This could not have been the beginning. In all its structure it tells us of something earlier and far simpler, but what this earlier ancestor was we do not know. Rather more highly organized relatives of the amoeba, the flagellata, have produced a membrane, and swim by means of vibratile, whiplash-like flagella. We must emphasize that these little animals correspond in all essential respects to the cells of our bodies; they are unicellular animals. And the cell once developed remains essentially the same structure, modified only in details, throughout higher animals. And these unicellular animals have the rudiments of all our functions. Their protoplasm and functions seem to differ from those of higher animals only in degree, not in kind. And the more we consider both these facts the more remarkable and suggestive do they become.

Cells with membranes can unite in colonies capable of division of labor and differentiation. And magosphæra is just such a little spheroidal colony. But the cells are still all alike, each one performs all functions equally well. But in volvox division of labor and differentiation of structure have taken place. Certain cells have become purely reproductive, while the rest gather nutriment for these, but are at the same time sensitive and locomotive, excretory and respiratory.

The first function to have cells specially devoted to it is the reproductive; this is a function absolutely necessary for the maintenance of the species. For the nutritive cells die when they have brought the reproductive cells to their full development. These few nutritive cells represent the body of all higher animals in contrast with the reproductive elements. And with the development of a body, death, as a normal process, enters the world. The dominant function is here evidently the reproductive, and the whole body is subservient to this.

only slowly lose

In hydra the union and differentiation of cells is carried further. But the cells are still much alike and their own individuality in that of the whole animal. This is shown in the fact that each entodermal cell digests its own particles of food, although the nutriment once digested diffuses to all parts of the body. Also almost any part of the animal containing both ectoderm and entoderm can be cut off and will develop into a new animal.

But beside the reproductive cells and tissues hydra has developed a very simple digestive system, in which the newly caught food at least macerates and begins to be dissolved. This is the second essential function. The animal can, and the plant as a rule does, exist with only the lowest rudiments of anything like nervous or muscular power; but no species can exist without good powers of digestion and reproduction. These essential organs must first develop and the higher must wait. And the inner, digestive, layer of cells persists in our bodies as the lining of the midintestine. We compared hydra therefore to a little patch of the lining of our intestine covered with a flake

of epidermis; only these layers in hydra possess powers lost to the corresponding cells of our bodies in the process of differentiation. Notice, please, that when cell or organ has once been developed it persists, as a rule, modified, but not lost. Nature's experiments are not in vain; her progress is very slow but sure. But hydra has also the promise of better things, traces of muscular and nervous tissue. There are still no compact muscles, like our own, much less ganglion or brain or nerve-centre of individuality. The tissues are diffuse, but they are the materials out of which the organs of higher animals will crystallize, so to speak. Notice also that these higher muscles and nerves are here entirely subservient to, and exist for, digestion and reproduction.

In the turbellaria the reproductive system has reached a very high grade of development. It is a complex and beautifully constructed organ. The digestive system has also vastly improved; it has its own muscular layers, and often some means of grasping food. But it is slower in reaching its full development than the reproductive system. But all the muscles are no longer attached to the stomach; they are beginning to assert their independence, and, in a rude way, to build a body-wall. But they are in many layers, and run in almost all directions. Some of these layers will disappear, but the most important ones, consisting of longitudinal and transverse fibres, will persist in higher forms. Locomotion by means of these muscles is slowly coming into prominence. They are no longer merely slaves of digestion.

But a muscular fibril contracts only under the stimulus of a nervous impulse. More nerve-cells are neces

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