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Show 452 DARWINISM CIIAP. man arc very numerous and exceedingly complex, somcti~cs one species, sometimes another agreeing mo t . ~early . wit? ourselves, thus presenting a tangled web of affimt1es wluch It is very difficult to unravel. Estimated by the skeleton alone, the chimpanzee and gorilla seem nearer . to man . tha-n the orang, which last is also inferior as presentmg certam a?err~tions in the muscles. In the form of the car the gonlla 1s more human than any other ape, while in the ton~ue the oran()' is the more ma.n-like. In the stomach and hver the gibb~ns approach nearest t~ man, then come the ?rang and chimpa.nzee, while the gonlla has a degraded hver more resembling that of the lower monkeys and baboons. The Brains of JJfan and A pes. \Ve come now to that part of his organisation in which man is so much hicrher than all tho lower animals-the brain j and here Mr. Mi~a.rt informs us, the orang stands highest in rank ' The height of the orang's cerebrum in front is greater in proportion. tha-n in ei~hcr the chi~panzee o; the gorilla. "On comparmg the bram of man with the brams. of the orang, chimpanzee, and baboon, we .find a successive decrease in the frontal lobe, and a successive and very grea-t increase in the relative size of the occipital lobe. Concomitantly with this incr~ase. and dccrea.sc, c~rtai.n f?lds of brain substance, called 'bndgmg convolutiOns, whi~h m man are conspicuously interposed bctwe~n the J?anetaJ ~ncl occipital lobes, seem as utterly to disappear m the chimpanzee, as they do in the baboo~. In th~ ?ran$, however, though much reduced, they arc still to ~e .distmgmshed ..... The actual and ab. olute mass of the bram Is, however, slightly greater in the chimpanzee than in the orang, as is the relative vertical extent of the middle part of the cerebrum, although, as already stated, the frontal portion is high~r in. the orallg j while, according to M. Gratiolet, the gonlla 1s not onl1 inferior to the orancr in cerebral development, but even to h1s b . "1 smaller African congener, the chimpanzee. On the whole, then, we find that no one of th.e great apes can be positively asserted to be nearest to man 1~ ~tructu~·e. Each of them approaches him in certain charactenst1cs, wh1le 1 Man and Apes, pp. 138, 144. XV DARWINISM APPLIED TO MAN 453 in. others it is widely removed, giving tho idea, so consonant With th.e theory of evolution as developed by Darwin, that all are denv.ed from a common ancestor, from which the existing anthropmd apes as well as man have diverged. When, however, we turn from tho details of ana-tomy to peculiarities of external form and motions, we find that, in a variety of characters, all these apes re emble each other and differ from man, so that we may fairly say that, while they have diverged somewhat from each other, they have diveraecl much more widely from ourselves. Let us briefly enu~erato some of these differences. Exte'rnal Differences of Man and Apes. All apes have large canine teeth, while in man these are no lo.nger than the adjacent incisors or premolar , tho whole forn~mg a perfectly even series. In apes the arms arc proportiOnately much longer than in man, while the thighs are ~nuch shor~er. No ape . tands really erect, a posture which IS natnral 111 man. The thumb is proportiona,tcly larger in man, and more pe~fectly opposable than in that of any ape. Th~ foot of man differ largely from that of all apes, in the honzontal solo, the projecting heel, the . hort toes, and the powerful great toe firmly attached parallel to the other toes j all perfectly. aclap.tod for ma.i~taining the erect posture, and for free motwn Without any md from the arm. or hands. In apes the foot is formed almost exactly like onr hand with a large thumb-like great toe quite free from the oth01: toes and so articulated as to be onl)Osablc to them · formincr with . y ) b tho long finger-like toes a perfect grasping hand. The sole canno.t be placed horizontally on tho ground j but when stanclmg on a. level surface the animal rests on the outer edge of .the foot With the finger and thumb-like toes partly closed, while the hands are placed on the ground rostincr on the k~ucldes. The illu ~ra~i?n on the next page (Fig. 37) shows, fa1rly well, the pecuhantws of the hands and feet of the chimpanzee, and their marked differences, both in form and u e, from those of man. The four limbs, with the peculiarly formed feet and hands, nrc those of arborea,l animals which only occasionaJly and awkwardly move on level ground. The arms are used in pro- |