THE CANADIAN ENTOMOLOGIST. 189 



A NEW CULICID GENUS RELATED TO CORETHRA. 



BY D. W. COgUlLLETT, WASHINGTON, D. C. 



The genus Corethra ^?^?. founded by Meigen in 1803,* on Tipula 

 culicifonnis, De Geer, and in April, 1844, Loevv erected the genus 

 Mochlonyx,-\o\\ Corethra velutina, Rutlie, basing it on the shortened first 

 joint of the tarsi, a character mentioned by Ruthe in his original descrip- 

 tion. The characters of the tarsi of cidiciformis cannot be ascertained 

 from De Geer's description and figures.! On page 386 of the same volume 

 of his Memoires, which contains the account of this species, is a descrip- 

 tion and brief account of a related species, which he named Tipula 

 crystallina, with a reference to Reaumur's Memoires, V., plate 6, figures 

 4-15, where, at 4 and 7, a more slender larva without a trace of a subanal 

 respiratory tube is shown; contrasting with the broader larva furnished with 

 a large respiratory tube, as represented in De Geer's figures oi culiciformis ; 

 the descriptions and figures which these authors give of crystallina do not 

 indicate the characters of the tarsal joints of the adult. Thus matters 

 stood at the time that Loew erected his genus Mochlonyx, and continued 

 so until the year 1S83. 



In that year Dr. Fr. Meinert, of Copenhagen, published the results of 

 his breeding of the adults from these two forms of larvae,§ asserting that 

 the tubeless larva of crystallina produced an adult with elongated first 

 tarsal joints as in Corethra in the sense of Loew, whereas the adult bred 

 from the larva of culiciformis had the very short first tarsal joints of 

 Mochlonyx. Some of the adults last mentioned were submitted to V. von 

 Roder, of Hoym, Germany, an experienced dipterologist, who confirmed 

 their reference to Mochlonyx}\ adding that, with the exception of having 

 the hairs on the abdomen and legs shorter, they are identical with Ruthe's 

 species, two specimens of which were in his collection, received from 

 Ruthe himself. It seems very certain, therefore, that the type species of 



*Illiger's Magasin, II., p. 260. tEnt. Zeiu Stetiin, p. 121. JMemoires, VI., p. 

 372, pi. 23, figs. 3-12. gOvers. Kon. Danske Vid. Selsk, Forh., pp. 1-17, and 

 Resume, pp. 7-1 1. ||Entom, Nach., July, 1885, p. 217. 



