apes and other members of the order primates, is then incorrect; and there is in this respect no essential difference between apes and man. Much has been said by opponents of the doctrine of the common descent of man and the lower animals in regard to the differences between the brains of men and of apes. But Professor Huxley, after reviewing and comparing their brain-characteristics, goes on to say,

"So far as cerebral [brain] structure goes, therefore, it is clear that man differs less from the chimpanzee or the orang than these do even from the monkeys, and that the difference between the brains of the chimpanzee and of man is almost insignificant when compared with that between a chimpanzee brain and that of a lemur." 1

The same thing is true of the differences in size of brain. The largest healthy human skull on record had a capacity of one hundred and seventeen cubic inches; 2 the smallest brain of an adult with sound mind measured sixty-two cubic inches; while the brain of the gorilla has been found to measure thirty-four and a half. There is, then, more difference in bulk between the largest and the smallest healthy human brain than between the latter and that of

1 Man's Place in Nature, p. 120.

2 Skull of male adult Indian, a basket-maker, killed during the American Revolution on Onion (now Winooski) River, ncar Bristol, Vt. Its internal capacity was nearly 117.2 cubic inches.

the gorilla. And again: in regard to the bulk of the brain Huxley says, "The lowest apes differ as much, in proportion, from the highest as the latter does from man." Yet, in making this statement so positively, Professor Huxley does not, nor does any capable judge of the matter, deny the existence of an extremely large number of details in which man is anatomically different from the ape. From a multitude of such details of structure, any comparative anatomist could distinguish the skeleton of a man from that of any other animal in the order primates. In the muscles, too, and in many other parts, there are plenty of slight differences between even the highest apes and man.1

But it is often claimed that the gap between the mental powers of man and of the most in. telligent of the animals below him is too great ever to have been bridged over by natural causes, and that, even if the descent of man's physical nature from a common ancestry with that of the

1 Yet Professor Owen, one of the strongest opponents of the theory of the common descent of man and apes, says, – "I cannot shut my eyes to the significance of that all-pervading similitude of structure, - every tooth, every bone strictly homologous [corresponding], — which makes the determination of the difference between Homo [man] and Pithecus [ape] the anatomist's difficulty," Journal of the Linnæan Society, London, 1857.

apes were to be admitted, we must still suppose the human mind to have been derived from some other source and in some supernatural way. It has, however, been shown by Darwin, in his Descent of Man," by Herbert Spencer, in his

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Biology," "Sociology," "Psychology," and "Ethics," as well as by the writings of Edward D. Cope and Chauncey Wright, that most, if not all, the mental and moral faculties of man may have been developed in a purely natural way.

Without the able explanations of the authors just quoted, however, it might readily be imagined that the apparent difficulty would prove susceptible of some natural solution; since the mental interval between man and apes is no greater than that between members of the same great groups in other divisions of the animal kingdom. No chasm, for instance, could well be wider than that between the ants and certain other insects, as the scale-insects.1

Ants have been found to possess a very acute touch, a keen sense of smell, and fair eyesight (at short distances). They are able to convey ideas to each other by means of their antennæ, or feelers, in such a way as to give and receive

Scale-insects are very abundant on bark, leaves, and some kinds of fruit: they may commonly be found on the bark of · apple-trees, appearing as little circular, close-clinging scales.

intelligence very quickly and accurately. They build houses, roads, and tunnels, make gardens, hold slaves, and even keep plant-lice (much in the same way as men keep cows), and milk and feed and take care of these domesticated insects. Says Sir John Lubbock,

“In face of such facts as these,1 it is impossible not to ask ourselves how far are ants mere exquisite automatons; how far are they conscious beings? When we see an ant-hill, tenanted by thousands of industrious inhabitants, excavating chambers, forming tunnels, making roads, guarding their home, gathering food, feeding the young, tending their domestic animals, each one fulfilling its duties industriously and without confusion,it is difficult altogether to deny to them the gift of reason; and the preceding observations tend to confirm the opinion that their mental powers differ from those of men not so much in kind as in degree." 2

On the other hand, the full-grown scale-insect consists simply of an oval, convex scale, destitute of feet, and clinging motionless to the leaf, bark, or fruit of the plant on which it feeds, showing no signs of sensation, much less of intelligence.

If the insect just described can be properly ranked in the same class with ants, there is certainly no difficulty in ranking man, even in view of his intellectual and moral nature, among mammals; and, if a naturalist does not

1 Behavior of ants which points clearly to the possession of something approaching to language.

2 Ants, Bees, and Wasps, by Sir John Lubbock, Appleton's International Scientific Series No. xlii., p. 181.

reject the theory of descent in the former case, he certainly need not do so in the latter.

It would hardly be fitting in any summary, however brief, of the facts which tend to prove man's community of origin with the apes, to omit some notice of the fact that idiots not infrequently present striking instances of reversion to what may fairly be taken to have been the characteristics of an ape-like ancestry. A low, retreating forehead, projecting jaw, prominent canine teeth, and slender, claw-like fingers are some of the physical traits of certain idiots. Along with these features, and probably as a consequence of the small (and ape-like) brain, one sometimes finds the uncontrolled curiosity, the continual movements, the incessant chattering and screaming which we are accustomed to associate with monkeys.

For many curious and important bodily and mental traits, in which man appears to display his community of origin with the lower animals, the reader must consult such works as Darwin's "Descent of Man," or Haeckel's "Evolution of Man." Lack of space makes it necessary in this half-chapter to stop short with a general statement of the nature of the known facts

See, also, Professor Frank Baker's lecture, What is Anatomy? New York Medical Journal, Oct. 22, 1887.