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THE POPULAR SCIENCE MONTHLY. 



clumsily. Try to flex a single toe, keeping 

 the rest straight, and the thing will be found 

 to be impossible ; they all move together. 

 The big toe may have a little independence, 

 but not much. The Buke of Argyll has 

 lately said, that we can know the animal 

 by looking down from our higher selves 

 upon our lower selves. If the duke would 

 look at an opossum flexing its toes in climb- 

 ing, and then look down on his own foot, 

 he would have a closer acquaintance with 

 the marsupial. Our toes have the same 

 communal movements as those of the opos- 

 sum. But our fingers we can flex one at a 

 time or any way we like. 



Now, Dr. Barnard's dissections would 

 seem to show that the muscles which move 

 the fingers and toes have been differentiated 

 from one (communis) muscle. He has found 

 many stages of differentiation. The flexor 

 which inserts in the thumb of man inserts 

 in two or three toes in the higher apes. 

 The extensor of the index-finger is the 

 same in the gorilla as in man, but in the 

 lower apes and lemurs it has two parts. In 

 lemurs the third finger gets a tendon from 

 the extensor of the index. In all apes the 

 extensor muscle of the third finger is in- 

 constant. On the theory that the proprius 

 muscles, the flexors and extensors of the 

 fingers and toes, have been developed by 

 specialization out of one communis muscle, 

 these facts and many others of the same 

 kind are luminous ; on any other theory 

 they are inexplicable. In the foot, man re- 

 mains a creature of the past, not modified 

 by that which makes him a man, the brain. 

 The hand has been modified and perfected 

 by its services to the brain. 



Tlie Orang and Man. Dr. Barnard's 

 paper on " The Myology of Simla satyrus''^ 

 was based on a dissection he had made of 

 an orang at Cornell University, and dis- 

 sections of lower apes recently made in 

 Germany. When, in 1818, Traill dissected 

 one of the higher apes, he found a muscle 

 which hehomologized with i\x& gluteus mini- 

 mus (one of the abductor muscles of the 

 thigh) in man. Other muscles in the same 

 region he supposed to represent similar 

 muscles in man. But one muscle he found 

 in the ape, which he thought had no repre- 

 sentative in man, and this he named the 



scansorius, or " climbing-muscle." Traill 

 was followed by Owen, Wyman, Wilder, 

 and by Bischoff, who, in his controversy 

 with Huxley, argued from this muscle 

 against a simian ancestry for man. Dr. 

 Barnard shows that Traill was mistaken, 

 and that the other great anatomists were 

 misled by the weight of his authority. 

 What Traill took to be the gluteus minimus 

 is the pyriformis, and what he figured as a 

 new muscle separating the apes from man, 

 the scatisorius, is the homologue of our glu- 

 teus minimus. In the orang. Dr. Barnard 

 finds a muscle which has no homologue in 

 man. It is a mere vestige. It occurs in 

 some of the lower apes, as the lemurs, but 

 has no functional value. It is found in the 

 opossum, but no longer as a vestige. Thus 

 when we go back as far as the marsupials, 

 this muscle, which in man is obsolete, almost 

 obsolete in the higher apes, less aborted in 

 the lower apes, is an active organ, perform- 

 ing certain functions. In the orang the two 

 external muscles of the calf do not unite to 

 form one tendon, tendon Achillis, as in man. 

 Now, this double tendon Achillis sometimes 

 occurs in marsupials. These researches go 

 far to prove that the muscles of man can 

 be traced backward through the apes to the 

 lemurs, and through them to the marsupials. 



Tlie Stndy of Mathematics. Prof H. A. 

 Newton, vice-president of Section A, at the 

 Detroit meeting, advocated in his address a 

 wider and deeper study of mathematics by 

 American men of science. American con- 

 tributions to the science of quantity have 

 not been large ; take away from their num- 

 ber three or four volumes, a dozen memoirs, 

 and here and there a fruitful idea, and there 

 is very little left that the world will care to 

 remember. True, excellent text-books have 

 been made here ; but Prof. Newton is speak- 

 ing of additions to our knowledge and not 

 of the arrangement of it. The idea seems 

 to be quite general among us that the 

 mathematics is a finished science, and that 

 it has few fertile fields inviting labor, and 

 few regions to be explored. And yet hard- 

 ly any science can show on the whole a more 

 steady progress for the last fifty years, or a 

 larger and healthier growth, than the science 

 of quantity. The scientific investigator imds 

 himself again and again arrested in his re- 



