246 SCIENCE PROGRESS. 



which had the same father. The immunity possessed by 

 the offspring is less than that of the father, but unlike the 

 immunity conferred by blood serum or milk this state is 

 permanent. 



A series of observations on the heredity of immunity 

 have been undertaken by Gley and Charrin (49). Rabbits 

 rendered immune to infection with the bacillus pyocyaneus 

 were paired and the offspring tested. The experiments 

 indicate that there is only occasional evidence of partial or 

 absolute immunity. They consider that this is dependent 

 entirely upon the male, for immune females tend to become 

 sterile, and to produce immature or malformed offspring. 

 In this they see strong evidence against accepting Weis- 

 mann's theory of heredity. 



Sufficient experimental work does not at present exist 

 to permit of any definite attitude on this question of inherited 

 immunity. Natural peculiarities, acquired characters and 

 mutilations are apparently never transmitted, and the con- 

 siderable literature which has grown up around this dogma 

 leaves it absolutely uncontradicted. Certain diseases 

 among white races, such as measles, small-pox and other 

 inoculable diseases, seem to have lost something of their 

 former virulence. 1 Yellow fever also is said to spare the 

 negro and destroy the mulatto. In all these cases instead 

 of a direct inheritance of susceptibility or of immunity it 

 is at least possible that while receptive families have died 

 out refractary families have succeeded in multiplying and 

 maintaining their existence, and consequently have raised 

 comparatively immune generations. 



1 Diseases such as small-pox, measles and syphilis were unknown 

 among savage races until introduced by Europeans. For the marked 

 susceptibility of savages see Bonwick, Last of the Tasmanians, and the 

 Black War of Vari Diemen's Land, 1870, and Moseley's Notes by a 

 Naturalist on the " Challenger" 1879, p. 341. 



