824 A N INTROD UCTION TO ENTOMOLOGY 



This is a comparatively small family. Malloch ('14) in his 

 "Catalogue of North American and Central American Simuliidae" 

 lists 3 8 species. The species that have attracted most attention in the 

 United States are the following. 



The Adirondack black-fly Prosimulium htrtipes. — This is a widely 

 distributed species but it has attracted most attention in the moun- 

 tains of the Northeastern States, where fishermen find it to be a 

 scourge in May and June. In this species the radial sector is dis- 

 tinctly forked. 



The southern bufi'alo-gnat, Cnephia pecudrum: — This is the 

 "Bufialo-gnat" of the Mississippi Valley, which in the past has been 

 a terrible pest of mules and other domestic animals, sometimes caus- 

 ing their death • but it seems to be much less common now than in 

 former years. In this species the radial sector is very indistinctly 

 forked at the apex. The popular name of this insect refers to a fancied 

 resemblance in the shape of the insect when viewed from one side to 

 that of a buffalo. 



The turkey-gnat, Siniulhim meridiondle. — This species closely 

 resembles the preceding in habits, infesting all kinds of domestic 

 animals, especially in the Mississippi Valley. As it appears at the 

 time that turkeys are setting and causes great injury to this fowl, it 

 is commonly known as the turkey-gnat. In this species the radial 

 sector is not forked. 



The white-stockinged black-fly, Simulium venustum.- — This 

 species is widely distributed and is one of the more common species 

 of the genus. It can be distinguished from the other species men- 

 tioned here by the fact that the tibiae are silvery white above. In the 

 Adirondacks it appears later than Prosimulium hirtipes and is not so 

 serious a pest. Professor Needham writes: "Guides have a saying, 

 that, when the black-flies put on their white stockings in June, the 

 trouble is about over. This species has the white stockings". 



The innoxious black-fly, Simulium ptctipes: — This black-fly is 

 very widely distributed and at Ithaca it is our most common species. 

 Although it may abound where during many summers I have taken 

 my classes for study of aquatic insects, I have never known it to bite. 



Family BLEPHAROCERID^ 

 The Net-winged Midges 



The net-winged midges are extremely remarkable insects; for in 

 certain respects the structure of the adults is very peculiar, and the 

 larvas appear much more like crustaceans than like insects. 



The adults are mosquito-like in form; but they differ from all 

 other insects in having the wings marked by a net -work of fine lines 

 which extend in various directions and are not influenced at all by 

 the veins of the wing (Fig. 1048). They are, however, quite constant 

 in their position in the species that I have studied. 



When a wing is examined with a microscope, the fine lines are 

 seen to be slender thickenings extending along the courses of slight 



