A MOSQUITO WHICH BREEDS IN SALT AND FRESH WATER. 



By Chables S. Banks. 

 (From the Entomological Section, Biological Laboratory, Bureau of Science, Ma- 

 nila, P. I.) 



INTRODUCTION. 



The finding of members of a given species of animal breeding under 

 such different conditions as those which obtain in fresh and salt water, 

 especially where experiments have proved that a given lot of individuals 

 when found in salt water and transferred to fresh for purposes of observa- 

 tion, have invariably died before reaching maturity, becomes a matter of 

 the gravest economic importance ; more particularly so when the question 

 narrows itself down to the discovery of a pathophoric mosquito having 

 such habits. 



It was stated by me in a former publication 1 that while the majority 

 of mosquitoes breed in fresh water, and while few are known to breed 

 in the water of the sea, yet Myzomyia ludloioii Theob. is among this 

 number. This form of mosquito has been proved to be a transmitter 

 of malarial fever. The statement- was also made that this mosquito 

 had never been found in these Islands breeding in fresh water; that as 

 a result of transferring a large number of larva? from sea to fresh water, 

 all had died; and putting them into sea water at the point of saturation 

 likewise killed them. 



The interesting and crucial feature of this discussion develops as the 

 result of a trip to the mountain Province of Lepanto-Bontoe to investi- 

 gate an epidemic of malarial fever, said by the officials in that region 

 to be of the most pernicious type. 



Naturally, I expected to meet with another species of mosquito causing 

 malaria in this isolated and elevated region, but instead I encountered 

 adults of M. ludlowii Theob. in the dwellings during the first night of 

 my stay in Cervantes, the capital of the province, and I was greatly 

 astonished to find their larvae breeding in the greatest abundance in the 

 rivers and small streams of the vicinity, while a thorough search extending 



1 This Journal, Sec. B. (1907), 2, 513. 

 "hoc. cit. 



