MOSQUITOES IN GENERAL 11 



every three or fonr days. Dr. Woldert, of Philadelphia, 

 has kept adults for two weeks or more in a bottle with a 

 slice of banana, sprinkling- the gauze-covering- occasion- 

 ally with water. He has even kept them for from fifty 

 to sixty days, but this was in the fall of the year, and, as 

 ■we have elsewhere shown, mosquitoes hibernate in the 

 adult condition and the significant life-period of the 

 adult is the summer period. We know that they will 

 live through the winter, but we do not know whether, 

 under normal conditions, those hatching- in the spring 

 will live through even half the summer. There used to 

 be a current idea that when a female mosquito sucks a 

 full meal of blood she is never able to bite again, since 

 it was thought that she is unable to thoroughly digest 

 such a meal. This idea, however, has been completely 

 exploded in the experimental medical work, and a more 

 approximate estimate of the length of the adult life has 

 been reached in this experimental medical work, than 

 has been elsewdiere gained. The army surgeons who 

 have been working on the subject of mosquitoes and 

 yellow fever have shown, as, in fact, had Dr. Finlay be- 

 fore them, that the same mosquito will bite and suck 

 blood again and again, and Drs. Reed, Carroll, and Agra- 

 monte have demonstrated that the yellow-fever mosquito 

 will not convey the disease until at least twelve days 

 have elapsed since the time when it bit a yellow-fever 

 patient. In the case of Anopheles and malaria there 

 must be an interval of seven or eight days for the proper 

 development of the malarial organism in the body of the 

 mosquito, before the disease can be conveyed through a 



