574 GORILLA AND MAN CHAP. 
than some Gorillas. But the average is undoubtedly as stated. 
It is to be noted that there is a correspondence between cranial 
capacity and size of palate, the correspondence being converse, 1.¢. 
the greater the brain the smaller the palate. This applies to 
Man as compared with his Ape-hke relatives, but does not apply 
so accurately to the Gorilla, which has a more extensive palate 
than the Chimpanzee; its “ brute development ” is much greater 
than that of the Chimpanzee. Not only is the palate larger, but 
the molar teeth, slightly different in form, are also larger and 
stronger. This is so plainly marked that “one may say almost 
with certainty, that any upper molar tooth over 12 mm. in 
length is that of a Gorilla, and under 12 mm. is that of a Chim- 
panzee.” In the skeleton generally it may be said that the 
crests for muscular attachments upon the bones are greater in 
the Gorilla. The nasal bones are more like those of lower Apes 
in their length, and they have a sharp ridge more marked than 
in the Chimpanzee, which, however, disappears in aged animals. 
It is a curious fact that Gorillas often have a “cleft palate,’ 
owing to the failure of the palatal part of the palatine bones 
to meet completely. The general conformation of the skull is 
less brachycephalic in the Gorilla. 
The lLmbs show a number of small differences, which are 
associated with a more completely arboreal life in the Chimpanzee 
as compared with the Gorilla. The latter is approaching the 
human way of life. In spite, however, of these differences, no 
hard and fast lines of divergence can be laid down between the 
two African Anthropoids, for it appears from the many memoirs 
that have been written upon both that “there is scarcely a 
feature in any muscle or bone found in one animal which is not 
also found in the other.” The heel of the Gorilla has already 
been referred to. This is, of course, associated with a plantigrade 
and therefore non-arboreal mode of progression. Certain of the 
muscles of the calf of the leg attached to the heel show a more 
human arrangement in the Gorilla than in the Chimpanzee. — It 
is interesting to find that the muscles of the little toe are 
diminishing in the Gorilla as in Man. This is most clearly due 
to terrestrial progression and we may apply the same explanation 
to Man and ignore tight boots! The arm of the Gorilla is less 
adapted to arboreal progression. Its proportions differ from those 
of the arm of the Chimpanzee in that the fore-arm is shorter. In ° 
