276 NEW YORK STATE MUSEUM 



often of a dull brownish tinge; in the males it projects beyond 

 the tips of the wings, is slender, cylindrical, or very slightly 

 tapered towards the tip, wdth some of the terminal segments sep- 

 arated by a strong contraction. 



This is a very common species, appearing upon the snow in the 

 winter season, and upon fences, windows, etc., in the fore part 

 of spring, the males and females being about equally numerous. 

 The beautiful plumose antennae of the former distinguish them 

 at a glance from all other insects abroad at this season. At times 

 they may be met with in immense swarms. 



Some specimens of larvae and adults from Gallinas river, Las 

 Vegas N. M. (altitude 6400 feet), do not appear to differ excepting 

 in being a little larger; the genitalia of the male resembles that 

 of D i a m e s a waltlii. It is possible that on examination of 

 more material the New Mexican form may prove to be a distinct 



species. 



9. Orthocladius stercorarius Degeer 



1776 Tipula Deg. Mem. pour serv. a I'hist. d. Ins. 6:388, 22 



1818 Chironomus Meig. Syst Beschr. 1 : 46, 57 



1850 Chironomus Zett Dipt. Scand. 9 : 3571, 97 



1864 Chironomus Scliiner. Fauna Austr. 2 :612 



1872 Cliironomus Holmgr. Of v. K. Vet, Akad. F(3rh. p.l05 



1874 Orthocladius V. d. Wulp. Tijds. v. Ent. 17 : 133 



1877 Orthocladius V. d. Wulp. Dipt. Neerl. p.279, 2 



1878 Chironomus Osten Sacken. Cat'l. Dipt. N. A. p.21 

 1898 Chironomus Lundb. Vidensk. Meddel. p.277, 58 

 1804 Chironomus chiopterus Meig. Klass. 1 ; 17, 18 



Wholly dull black; the antennae blackish brown, the hairs 

 scarcely lighter. Forceps of the male black. Legs blackish 

 brown, pitchy, or occasionally still paler; the fore legs bare; the 

 fore metatarsus only one half as long as its tibia. Wings milky 

 white. The halteres black or brown. The female has somewhat 

 darker wing and lighter abdomen. Length 1.5 to 2.75 mm. 

 Greenland. Holmgren and Lundbeck. 



10. Orthocladius atomarius Zetterstedt 



1850 Chironomus Zett Dipt. Scand. 9:3522, 40 

 1864 Chironomus Schiner. Faima Austr. 2 : 609 

 1884 Orthocladius Mik. Wien. Ent. Zeitg. 3:202 

 1898 Chironomus Limdb. Yidensk. Meddel. p.283, 68 



Resembles O. sordidellus, but is much smaller and the 

 structure of the tarsi is different. Thorax brown, subshining, 

 the dorsum usually yellowish, light brown or testaceous, with 

 three nearly confluent dark stripes ; metathorax black. Abdomen 



