DISCUSSION OP THE PROBLEM. 109 



most serious discomfort, and its sanguinary appetite, can 

 be imao'ined rather than described when we are made fa- 

 miliar by personal experience with its habits. The grada- 

 tions, too, between such mere inconvenience or irritation, 

 and serious consequences arising from its bite, can be in- 

 definitely expanded. The wound that brings about a tem- 

 porary inconvenience may, under other circumstances, be- 

 come a swelling, lasting for some time, tending to dimin- 

 ish vitality or retard recovery from disease. These effects 

 can become more and more important, more and more per- 

 manent and pernicious, until we reach such a possibly ag- 

 gravated state of things, wherein exhaustion may disturb 

 the delicate balance between life and death. 



Dr. Findlay, of Havana (see Science, Vol. VIII., page 

 279), has brought the more unnatural charge against the 

 mosquito, that it is an agent in spreading yellow fever. 

 Dr. Findlay asserts that it is his belief that the insect, after 

 puncturing the skin of a yellow fever patient, retains some 

 of the germs of the disease, which are communicated to its 

 next host. Similarly the young of mosquitoes breeding in 

 neighborhoods afflicted with the disease would even be- 

 come the carriers of its germs. So convinced is Dr. Find- 

 lay of this that he avers that the mosquito is the active, 

 if not the sole, agent for the dissemination of yellow fever, 

 and he believes that where the mosquito cannot live, or, 

 at the season when it decreases in numbers, the yellow 

 fever simultaneously disappears. In corroboration of this 

 he says that in the summer of 1885 mosquitoes were scarce 

 in Havana, but were very numerous in the autumn ; and 

 that yellow fever cases were few in number, but in October 

 and November they increased considerably, at which times 

 the mosquitoes appeared. In coufirmatiou of this view 



