429 



in base of second posterior cell, touching the cross vein and the pos- 

 terior side of third vein, and carried as a more or less distinct suffu- 

 sion into the third posterior cell ; the spot in fork of cubitus carried 

 over into anal cell in the area between the base and apex of posterior 

 branch of cubitus ; spot in anal cell almost indistinguishable. Halteres 

 yellow, knob almost entirely blackened. 



The basal joint of fore tarsi is twice as long as fore tibiae (30 : 

 15). Otherwise as H^^c/Aa mi. 



Length, 1.5 mm. 



Type localitv, Momence, 111.. July 17. 19 14- ''^t light (C. A. Hart). 

 Paratype f rom Plummer's Island. Md.. August 17. 1912 (W. L. Mc- 

 Atee) ; in collection of the U. S. Bureau of Biological Survey. 



6. Chironomus perpulcher Mitchell 



Chironomus perpulcher Mitchell, Jour. N. Y. Ent. Soc, 1908, Vol. 16, p. 13. 



This species is readily distinguished from any other described 

 American species of this genus by the wing-markings (see PI. XXXV, 



Fig- 4)- 



Illinois localities : Mt. Carmel, June 30, 1906, St. Joseph, June 9, 



1912, and Monticello. June 21-30. 1914; Urbana, July 7, 1914 (C A. 



Hart and J. R. Malloch). 



Originally described from examples taken at Plummer's Island, 

 Md., in August. I have seen specimens taken at Lafayette, Ind., m 

 June and August (4th) by Professor Aldrich. 



The early stages are undescribed. 



7. Chironomus pulchripennis Coquillett 



Chironomus pulchriperuiis Coquillett, Proc. U. S. Nat. Mus., 1902, Vol. 2.5, p. 94. 



This species is very closely allied to tccniapcnnis, but the wing- 

 markings serve to separate them most readily. (See PI. XXX\_, Fig. 

 5.) Johannsen says: "seems to be a synonym of tccmapennis Coq., 

 but I regard the species as distinct. 



Represented in the collection here by a single female from Algon- 

 quin, August 31, 1894 (Nason). 



Originally described from Franconia. N. H. 



The early stages are undescribed. 



8. Chironomus nephopterus Mitchell 



Chironomus nephopterus Mitchell, Jour. N. Y. Ent. Soc. 1908, Vol. 16, p. 7. 



The wing-markings of this species and those of tccmapennis are 

 almost identical. The characters given in the synoptic key herewith 



