DIFFEBENOES OF MAN FROM THE APES 635 



spheres, which are also nauch larger compared witli the cere- 

 bellum, and completely cover the latter ; the entire brain 

 being at least double the size proportionately of that of the 

 goi'illa ; * it is also stated that two muscles exist in man 

 which have not yet been found in any ape, the extensor primi 

 iiiternodii poUicis and the peronwus tertius, belonging to the 

 thumb and foot respectively (Huxley), f There are also points 

 in the origin of certain muscles which are peculiar to man, but 

 Huxley adds that all the apparently distinctive peculiarities 

 of the muscles of the apes are to be met with, occasionally, 

 as varieties in man. On the other hand, the relative differ- 

 ences of the skulls of the gorilla and man are, as Huxley 

 states, "immense." In man the cranial box overhangs the 

 orbits ; in the gorilla the forehead is hollowed out. The 

 hinder jiortion of the brain is also much more develoj^ed in 

 man than in the apes, and in the hinder part of the hemi- 

 spheres the convolutions are more numerous than in the 

 chimpanzee, this part in monkeys losing its convolutions 

 altogether (Wyman). Man stands erect ; liis arms span a 

 distance equal to his height ; the spinal column has four 

 curves ; the skin of the hands and feet of man is highly 

 sensitive, compared with tliat of the apes. Finally, as Cuvier 

 stated, the grand distinctive zoological character separating 

 man from the other animals is the possession of the power of 

 speech. 



Sometimes in man the coccyx has one or two more Joints 

 than the normal number, but the apes have no tail ; though 

 the human embyro, like other young animals, has a tail, 



* " It must not be overlooked, however, that there is a very striking 

 difference in absolute mass and weight between the lowest human 

 brain and that of the highest ape — a difference which is all the more 

 remarkable when we recollect that a full-grown gorilla is probably 

 pretty nearly twice as heavy as a Bosjes man, or as many an European 

 woman. It may be doubted whether a healthy human brain ever 

 weighed less than thirty-one or two ounces, or that the heaviest gorilla 

 brain has exceeded twenty ounces." In another place Huxley states 

 that "an average European child of four year's old has a brain twice 

 as large as that of an adult gorilla." — Man's Place in Nature. 



\ Dr. Chapman has found in the arm of a gorilla a distinct extensor 

 primi internodii polUcis muscle, but no trace of the flexor longus poUi- 

 cis.— American Naturalist, June, 1879, p. 395. 



