1879.] NATURAL SCIENCES OF PHILADELPHIA. 63 



upper occipital convolution in Man being more superficial than in 

 the ape. The upper occipital convolution, according to Huxley 

 and Gratiolet, is absent in the Chimpanzee, but has been found 

 at least on one side in the specimens described by Rolleston, 

 Marshall, Turner, and Broca. The upper and middle occipital 

 convolutions, so far as I have been able to compare them, seem to 

 correspond to the convolutions described under the names of 

 "Plis de passage," " Bridging," " Annectant gyri," and"Obere, 

 innere unci aussere Seheitelbogen-Windungen." The only other 

 peculiarity that I noticed in the Chimpanzee was in reference to 

 the parieto-occipital fissure of the right side, which did not reach 

 the calcarine, being separated by the "deuxieme plis du passage 

 interne" of Gratiolet, and that on both sides the calcarine lissure 

 passed into the hippocampal, so that the gyrus fornicatus did not 

 pass into the convolution of the hippocampus as in Man. In 

 this latter respect, however, Ateles Paniscus, one case of Hylo- 

 bates, and Turner's Chimpanzee agree with Man and disagree 

 with all the other monkeys. The mesial side or the base of the 

 brain did not present anything very different from Man, so far 

 as they were susceptible of examination. The nerves coming 

 from the base of the brain were, however, relatively very large. 

 With all deference to Prof. Bischoff, I cannot agree that the 

 " Klu ft zwischen der hohen Entwicklung der Grosshirnwindung 

 des Menschen und derjenigen des Oi'ang oder der Chimpanse liisst 

 sich nicht ausfullen durch Hinweisung auf die Kluft zwischen der 

 Entwicklung dieser Windungen zwischen dem Orang oder Chim- 

 panse und Lemur. Letztere ist ausgefiillt durch die zwischen 

 beiden liegenden Arten der Affen. Die Ausfullung der ersteren 

 muss noch gefunden werden." 1 On the contrary, it appears to me 

 that on the whole the gap between the brain of the Chimpanzee and 

 Man is less than that between the Chimpanzee and the lower 

 monkeys ; and, though it is not generally considered so, that the 

 brain of the Chimpanzee resembles that of Man quite as closely 

 as that of the Orang. 



Resume. In considering the Chimpanzee in the totality of its 

 organization, it appears to me to be as closely allied to Man as 

 the Gorilla, but it must be remembered that, like it, in the absence 

 of certain muscles, etc., the Chimpanzee and Gorilla are both less 

 like Man than the lower monkeys. 



1 Die Grosshirnwindungen, p. 492. Munich Aband. 1868. 



