MOSQUITOES. 189 



food it must be able to save itself when disturbed and it 

 does so the very moment the surface of the water becomes 

 agitated, by a few strokes with paddle-like swimming-or- 

 gans located at the tail. The trumpet-shaped breathing- 

 tubes contain upon their inner surface a large number of 

 peculiar hairs, which prevent the water from entering. Like 

 the larva the pupa has to come frequently to the surface to 

 breathe air, and if not disturbed always hangs suspended 

 from the surface-film of the water. In a few days the last 

 transformation takes place, which is well shown in (c). 

 The pupal skin splits open in the back, thus forming a boat, 

 and the adult and winged mosquito works its way very 

 carefully out of the many fine skins that enclose its various 

 members. As soon as the wings are expanded and dry the 

 insect flies away, now breathing air in the usual manner of 

 insects by means of fine openings located in the sides of the 

 thorax and abdomen. We have here the interesting fact 

 that the same insect has to breathe air in three different 

 ways and by three different sets of organs, each seen to be 

 most wonderful in structure if carefully studied by means of 

 a microscope. 



Thus far both sexes were very similar in structure, but 

 if we now study them in their winged shape we shall find 

 them quite different. The male {e) is distinguished by very 

 large and feather-like feelers, and by rudimentary mouth- 

 parts. The female {(7 and c) has smaller feelers, and a hard, 

 long and slender proboscis, decidedly well adapted to suck- 

 ing blood. Of course in nature but few of these bloodthirsty 

 females ever have an opportunity to obtain such food, and 

 they must subsist upon something else. It is suspected, and 

 the experiments made this summer but not yet finished seem 

 to prove it, that females inbibing such blood die in conse- 

 quence. Where is the benefit to the species if such is the case? 



Regions in which stagnant water abounds are famous, 

 or rather infamous, on account of the vast number of such 

 insects, and their presence is easily accounted for. But we 

 find them many miles away from water and sometimes in 

 equally large numbers. Where do they come from and where 

 do they breed ? 



