PHYSIOLOGY, AND PATHOLOGY OF THE CHIMPANZEE. 



419 



It has been shown by Metschnikoff, E,oux, ISTeisser, and Lassar 

 that the Chimpanzee is more susceptible to the virus of syphilis 

 than any other Ape or Monkey. The primary lesions appear 

 in thirty days after inoculation ; the secondary symptoms develop 

 after a f ui^ther peiiod of more than thirty days ; but tertiar}'^ 

 signs have never been observed. 



All experimental inoculations with the gonococcus have failed 

 to produce a result. 



Keith has collected papers by Owen (75, 76), Schmidt (77), 

 Rollet (78), and Meyer (79) on the pathology of the Chimpanzee. 

 And the works of Ehrlich and Hata give accounts of the trans- 

 missibility of yaws to Apes ; but the actual Apes employed have 

 not been mentioned. 



I desire to express my thanks to Dr. Doreen Stranger, Dr. 

 J. H. James, Miss Kahan and Messrs, Aurounin, Henderson, 

 Meneces, and McCormick, students in the Anatomy Department 

 of Univei'sity College, for their assistance in the dissection of 

 the animal described above. 



COMPAEISONS WITH MaN. 



The Ohimpai:izee resembles Man in a general way in form and 

 structure, but it differs from him in many i-espects. Some of the 

 differences are associated with habits and diet; others are 

 dependent on differences in the size and complexity of the brain ; 

 and others again are the outcome of different developmental 

 processes. 



At a certain stage the foetuses of the Chimpanzee and Man 

 have sevei'al features in common, but the subsequent develop- 

 mental changes — both intrauterine and extrauterine — proceed in 

 different directions. In the Chimpanzee they are marked by a 

 progressive increase in certain parts, such as the hair and facial 

 skeleton. In Man, on the other hand, they are characterised 

 by suppression ; but the power to develop farther lies dormant. 



