246 NEW YORK STATE MUSEUM 



Malaria. This disease is by far the most important of the 

 above named in New York State. Professor Herrick, in a recent 

 paper, concludes that " malaria is responsible for more sickness 

 among the white population of the South, than any disease to 

 which it is now subject." It is less important in New York, yet 

 this enervating disease is certainly responsible for large annual 

 losses, because all those infected are frequently unfitted for work, 

 though comparatively few deaths are attributed directly to it. It 

 is conveyed, as shown by various investigators, by members of the 

 genus Anopheles, of which we have three species, A. crucians, 

 A. maculipennis and A. punctipennis, the latter two 

 are probably agents in its distribution. These insects act only as 

 intermediary hosts, affor'ding the parasite which produces the 

 fever, favorable conditions for undergoing certain changes prior 

 to its introduction into the human system. It is impossible for 

 these mosquitos to convey malaria before they have become in- 

 fected by biting a malarious subject, and consequently the spread 

 of this disease is readily checked by either destroying all of the 

 insects capable of carrying it, or by keeping them from sources 

 of infection. Anopheles must exist where malaria occurs, though 

 it does not follow that the distribution of malaria is coincident 

 with that of Anopheles. 



Yellow fever. This dread disease of man is well known, and up 

 to within very recent years no adequate knowledge existed as to 

 the way in which it was spread. Dr Josiah C. Nott, of Mobile Ala., 

 published in the New Orleans Medical and Surgical Journal for 

 March 1848, a number of reasons why insects probably were agents 

 in carrying this disease. This was again advocated in 1881 to 

 1886 by Dr Finlay of Havana, and recent investigations in Cuba 

 demonstrated that it may be carried by a mosquito, Stegomyia 

 f a s c i a t a , and possibly by some other forms belonging to the 

 same genus. As in the case with malaria, the yellow fever mos- 

 quito is simply what is known as an intermediary host and must 

 first become infected with the parasite before it is capable of 

 imparting this dangerous disease. Control of these pests is so 

 important in Cuba that the genffl*al government spent about 



