455 



joint one third longer than tibia (80: 60), second joint slightly longer 

 than third; mid and hind legs with the hairs on femora and tibirc 

 about equal to the diameter of the joints which bear them. Third vein 

 almost straight, costa reaching beyond the beginning of apical curve ; 

 cross vein at wing-middle ; cubitus forking slightly distad of the cross 

 vein. 



Female. — Similar to the male in color except that the antennae have 

 only the apical joint fuscous and the legs have the black portions 

 rather broader, especially on the fore knees, where the bases of the 

 tibi?e are rather broadly black. 



The antennae are short, about equal in length to the palpi ; the body 

 is stouter than in the male, the abdomen particularly so, and the vena- 

 tion differs from that of the male in that the third vein is distinctly 

 curved. 



Length: male, 4-5 mm.; female, 3-3.5 mm. 

 Illinois locality, Momence, July 17, 1914. A series of five males 

 and four females taken at light by Mr. Hart. 

 Originally described from Ithaca, N, Y. 

 Early stages undescribed. 



36. Chironomus aberrans Johannsen 



CJiironomus aherrans Johannsen, Bull. 86, N. Y. State Mus., 1905, p. 221. 

 Chironomus fascipes Coqiiillett, Proc. Ent. Soc. Wash., Vol. 9, 1908, p. 145. 



Female. — Yellow, with a slight greenish tinge. Head yellow, an- 

 tennae concolorous, palpi fuscous. Mesonotum with reddish vittae, the 

 spaces between them slightly whitish pollinose ; postnotum blackish 

 brown. Basal 2-3 segments of abdomen greenish yellow, the others 

 blackish with pale posterior margins. Legs yellow, mid and hind 

 knees, apices of all tibiae and of the joints of fore tarsi narrowly 

 brown, apices of fore femora and bases of fore tibi'£ broadly brown. 

 Wings clear, cross vein not infuscated. 



Pronotum linear, not extending to upper margin of mesonotum, 

 the latter much produced above at anterior margin. Legs rather 

 stout, their surfaces with a few long hairs ; basal joint of fore tarsi 

 about a fourth longer than tibia (80:65). Cubitus forking very 

 slightly beyond cross vein. 



Male. — Agrees with the female in color except that the abdomen 

 has only the apical three abdominal segments blackened. 



The fore tarsi have no long hairs, and the hypopygium is very sim- 

 ilar to that of fallax (PI. XXXIII, Fig. 7) except that the superior 

 process is considerably stouter and less distinctly curved. 



