PROSIMULIUM. 21 



slender, without paired apical hairs; fore tibia) with weak apical 

 spur; hind tarsi with basal joint distinctly produced at apex (PL II, 

 fig. 18), second joint without scale but slightly constricted dorsally 

 at base; tarsal claws simple. Wings without fork to radius, the 

 small closed basal cell present; hairs on wing veins brownish black. 



Length, 3^ mm. 



Tijpe. — Cat. No. 15404, U. S. National Museum. 



Type locality, Glassboro, N. J., March 28, 1910 (C. T. Greene). 

 Paratypes from Clementon, N. J., May 7, 1910 (C. T. Greene) ; St. 

 Louis, Mo., April 6, 1904 (W. V. Warner) ; Kaslo, British Columbia 

 (H. G. Dyar) ; Mount Eainier, Wash. (M. W. Lyon, jr.) ; Sitka, 

 Virgins Bay, and Yakutat, Alaska, Harriman Alaska Expedition 

 (T. Kincaid) ; Metlakatla, Alaska. There is a specimen of this 

 species in the Illinois State Laboratory of Natural History collection 

 from Homer, 111., April 25, 1909. 



This species presents some characters which differ considerably 

 from those of the type of the genus {hirtipes)^ but I do not consider 

 it necessary to create a new genus for its reception, more particularly 

 because at least one character, and the most pronounced, the radial 

 furcation, is only indicated to a slight extent in pecuarum^ which 

 is clearly congeneric with hirtipes. Roubaud in subdividing Si- 

 muliufn used the tarsal characters and did not cite the types of his 

 genera. His Eusiinulium is clearly a synonym of Simulium^ as the 

 characters indicated for its separation from Prosimulium are those 

 possessed by the type of that genus, and the only species mentioned 

 by Roubaud as an example of Eusimulium is aureum Fries, which 

 possesses the tarsal characters given by him. He evidently consid- 

 ered it inadvisable to use Siniulmm as the name of one of his di- 

 visions, because he intended only to make use of these as subgenera, 

 and not genera. Surcouf and Gonzalez-Rincones ^ have, however, 

 used the three names and placed in the genus Eusimulium, which 

 they characterize as having the " second hind tarsal joint constricted," 

 a number of species which they evidently Imew only from the 

 printed descriptions. In Shmdium sens, strict, they include several 

 species which they evidently have never had an opportunity of ex- 

 amining, and which certainly possess the same tarsal characters as 

 those they relegate to EusimuUuiii. I have considered Roubaud's 

 genus as a synonym of Slmulium and also consider that the publica- 

 tion above referred to does not materially affect this position.- 



Prosirtiulium. pecuarum Riley. 



This species is similar in color and size to mutatuin, but differs as 

 follows: The pilosity on scutum and hairs on abdomen are whitish- 

 yellow, the scutum is more or less distinctly three-striped, the hind 



1 Dlpt^res vulerixnls des du Venezuela, I, 1012, p. 276. 

 -See footnote :! to p. 14. 



