AQUATIC I^'■SECTS IX NEW YORK STATE 361 



cording to Mr Coqnillett tlie species also occurs in Colorado and 

 Montana [pl.38, fig.21]. 



Moscow Id. (June 19). 



S. glaucum Coquillett 

 U. S. Nat. Mus. Proc. 1902. 2.j:97 

 Male. Head and body black, lace gray pruinose, thorax bluish 

 gray pruinose, mesonotum marked with a narrow median and 

 slightly wider lateral black vittae, broad lateral margins, when 

 A'iewed from behind silvery white, a pair of large subquadrate 

 spots on the front end separated by the median black vitta, 

 which is here greatly dilated; abdomen velvet black, sides of 

 segments two and five to nine silvery, middle of dorsum of four 

 also silvery; venter almost wholly silvery; femora and tibiae 

 brown, bases of tibiae yellow, anterior side of front ones largely 

 silvery; tarsi black, broad base of first joint of the middle and 

 hind ones whitish; wings hyaline, veins along the costa yellow- 

 ish brown, the others iK^arly hyaline; lialteres yellow; length, 

 2.5mm. 



In April. Kansas City, Missouri. 



S. griseum Coquillett 

 Dep't Agric. Div. Ent. Bui. 10, n. s. 1898. p.69. Colorado 



Female. Front and middle femora and tibiae wholly yellow, 

 hind ones except their apexes also yellow, tarsi brown, bases of 

 the first two joints of the middle and hind ones yellow; 

 mesonotum grayish, indications of a darker median vitta, the 

 sides and front corners yellow, pleura light gray, sciitellum yel- 

 low; abdomen gray, segments 2 to each marked with three vel- 

 vet-black spots; wings hyaline, the costa, first three veins, and 

 first section of the fourth, yellow, the others subhyaline; face 

 and front light gray, antennae brown, the two basal joints yel- 

 low, palpi black, proboscis yellowish. Length 1.5mm. Colo- 

 rado. Three females, collected by ]Mr Carl F. Baker. 



Male. Center of mesonotum with a narrow black vitta, 

 mesonotum elsewhere gray, dorsum of abdomen velvet-black, 

 the second and seventh segments and a spot on the sides of the 

 eighth, silvery gray, otherwise as in the female. A male taken 

 with the female specimens. 



S. hirtipes Fries 



Obs. entomol. Tars 1. Mouogr. Simiiliar. 1824. 17:5, Tfl. 1, f.l. 



1830 r u f i p e s Meigen, Syst. Besebr. 6:311-17 



1830 hirtipes Fries, Meigen. Syst. Besebr. 6:312-18 



1850 birti pes Fries, Zetterstedt, Dipt. Scand. 9:3426-28 



