296 THE PRESENT EVOLUTION OF MAN — PHYSICAL 



" The conditions under which the individuals live here 

 are in both cases practically the same. The difference, 

 therefore, does not appear to arise from any factor 

 acting immediately and directly on the individuals, but 

 to be connected with something more remote. _ To me 

 there seems but one solution of the matter ; the peculi- 

 arity depends upon inherited differences, in fact, on 

 racial characteristics." — Dr. Grieve, British Guiana 

 Medical Annual, March 1, 1890. 



I have not been able to gather anything very definite 

 concerning the Chinese in their relation to tubercu- 

 losis ; but considering how many and large are their 

 cities, how ancient their civilization, how filthy their 

 habits, and how crowded their dwellings, especially the 

 sleeping apartments, they should be of all the races 

 of the world the most resistant, if not against tubercu- 

 losis, which infests in particular houses of the Euro- 

 pean type, yet against many other non-malarial zymotic 

 diseases. 



Measles. — Since measles, though very prevalent, is not 

 very fatal, at least not so fatal as either malaria or tu"ber- 

 culosis, evolution against it is not nearly so marked as 

 against either of those diseases. Its microbes secure 

 their specific persistence by a rapid passage from host 

 to host, and by an enormously rapid rate of multipli- 

 cation. Nevertheless, all observers are agreed in declar- 

 ing that it is more fatal when afflicting races to which it 

 is strange than it is when afflicting races to which it 

 is familiar — i. e. it is sufficiently death-dealing to have 

 caused some evolution against itself. But all observers 

 are also in agreement in thinking that the greater 

 malignancy of type it displays when attacking the 

 natives of the New World is to be attributed to im- 

 proper medical treatment of the sick, or to lack of 

 treatment rather than lack of resisting power. From 



