390 THE HUMAN SPECIES 



II. Special Pathology and Pathological Anatomy. 



In the foregoing pages the outlines of general human and 

 animal pathology and of pathological anatomy have been 

 described. Special pathology and pathological anatomy will 

 now be dealt with and similarly compared ; we shall see in 

 what way man occupies a special position, and in what way he 

 resembles other animals. 



In order to make our survey clearer, internal pathological 

 conditions will be divided into infectious and non-infectious 

 diseases, and these again subdivided. This will be followed by 

 a short comparative description of surgical diseases, of diseases 

 of the eye, nose and ear, and finally by an account of compara- 

 tive obstetrics. 



i. Internal Diseases. 

 (a) Infectious Diseases. 1 



Cholera, the organism of which was described by Koch in 

 1883 (Plate V., fig. i), is only seen primarily in man. Spon- 

 taneous cases do not occur among animals. The cases of a 

 chimpanzee and other animals in the Zoological Gardens of 

 Antwerp and Amsterdam, which were reported by M. Schmidt 

 during the cholera epidemic in those towns of 1830 and 1831, 

 cannot be regarded as genuine merely because the animals 

 exhibited choleraic symptoms. Watery stools, vomiting, thirst, 

 dry lips, bluish colour and coldness of the skin, and a small 

 and very rapid pulse are symptoms which may be set up 

 simply by acute intestinal catarrh. 



Experimentally, however, the majority of animals can be 

 infected by injections of human cholera stools or by pure 

 cultures. Guinea-pigs are especially susceptible. The animals 

 exhibit symptoms absolutely similar to those seen in man, 

 and post-mortem show the characteristic reddening and loss of 

 epithelium in the intestine (Marx). 



1 Friedberger und Frohner, Spcz. Pathologic der Haussdugetiere, 5th 

 edition. Stuttgart: F. Enke, 1900. Marx, Experimentelle Diagnostik, Serum- 

 therapie und Prophylaxe der Infectionskrankheiten. Berlin : A. Hirschwald, 

 1902. Schmidt, M., Zoologische Klinik. Berlin : Hirschwald, 1870, vol. i. ; 

 1872, vol. ii. 



