54 AGRICULTURAL EXPERIMENT STATION. 



These studies by Mr. Parker add materially to our definite 

 knowledge of the food of mosquito larvae, and do not bear out 

 the idea that the wrigglers are of material aid in purifying 

 water. Nevertheless, as Mr. Parker suggests, many organisms 

 would leave no trace in the stomach soon after digestion and the 

 only way to determine whether the larvse can actually subsist on 

 bacteria and similar organisms is by direct experiment, placing 

 carefully washed larvcC in a diluted culture of the organisms it 

 is desired to test. 



CHAPTER V. 

 HIBERNATION OF MOSQUITOES. 



Moscjuitoes may live through the winter in either the egg, 

 larval or adult stage, though the former is the most common 

 method for those belonging to our fauna. All our species of 

 Anopheles hibernate as adults, but I know positively of only 

 three species of Ciilex that they do so ; these are pipiens, restuans 

 and salinarius; all closely allied. Of Culex melanunis^ Core- 

 thrella brakeleyi and Wyeomyia smithii it is positively known 

 that they winter as larvae. Of the others we know, either that 

 they winter in the egg stage or we know nothing at all definite 

 about them. It is generally fair to assume that when no trace 

 of the species can be found in any other stage, that the egg lives 

 through that dormant period. 



This egg may be either in the mud of pools to be filled by the 

 snow and winter rains, or on the bottom of pools already filled, 

 ready, like that of canadensis, to hatch at the least provocation. 



The adults, when they hibernate, seek any shelter that will 

 protect them from the direct influence of the weather. Mr. 

 Brakeley has made an interesting- hunt for Anopheles and has 

 found them imder overhanging banks, among the roots of trees 

 and in "varmint" holes in sloping banks ; wherever, in fact, there 

 was opportunity for shelter. They, as well as the Culex, have 

 also been found in hollow trees and logs and, out-doors, there 

 seems to be no one place more especially favored than another. 

 In settled communities all these species favor the cellars of barns 

 and other buildings. In a vacant house specimens may be found 

 in any room; but the cellar usually contains more than all the 

 others taken together. In barns and other outbuildings they 



