146 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



species of house mosquitoes present in the region is Cule.r 

 rest nans Theob., and that is rare, and has not been reported 

 troublesome in any case. The region is far beyond the normal 

 range of Culex quinquefasciatus Say or Aedcs calopus Meig., 

 nor is there any likelihood of these being imported, as Dublin 

 is a three hours ride by train from Boston, where the occur- 

 rence of either of these insects is very occasional and dependent 

 upon a chance importation from the south. 



The group of woods mosquitoes is well represented in the 

 region. Aedcs stiinu/ans and its allies, the group of black- 

 legged species such as Acdes abscrratus F.&Y., trichurus Dyar, 

 lasarensis Felt,aurifcr Coq.,auroides Fe\t,fuscns Osten Sacken^ 

 etc., and Aedes canadensis Theob., as well as the tree-hole 

 inhabiting Aedcs triseriatns Say, are all present. The condi- 

 tions for their breeding are ideal, the rocky and hilly soil hold- 

 ing temporary pools of melting snow water in innumerable 

 places, besides the edges of all the marshes which occur in 

 nearly every valley not large enough to hold a lake. These 

 places are all dry during the summer, but are typical breeding- 

 places for the woods species. The continuous cover of low for- 

 est makes excellent camping-ground for the adults and enables 

 them to travel long distances without coming out into the hot 

 fields. It would seem, therefore, that these species should be 

 the principally troublesome ones. Such, however, is not the 

 case. Two causes tend to produce this result. In the first place 

 the woods mosquitoes never leave the shelter of trees for any 

 distance and so do not enter the houses, for the majority of 

 places have at least a small open space about the house. While 

 one might be eaten alive by these insects in the woods, another 

 upon the porch of a house would suffer no special inconven- 

 ience. In the second place these mosquitoes rapidly become 

 scarce as the season advances, since they have no second brood 

 after the first emergence in May, or at least but an insignificant 

 after-breeding in the case of Aedcs canadensis and A. fuscus, 

 while the the tree-hole A. triscriatus is not an important factor. 

 Thus by August, before which the summer residents have not 

 arrived to any extent, the woods mosquitoes have b n greatly 

 lessened in numbers. 



There remains, then, but one species as the principll source 

 of annoyance, namely Mansonia perturbans Walk. Tne adults 

 begin to emerge at the end of June and become abundant in 

 July, at the time when the summer visitors begin to arrive. 

 These mosquitoes are largely nocturnal, and do not hestitate 

 to enter houses, coming in freely through the chimneys when 



