170 MAINE AGRICULTURAL EXPERIMENT STATION. I9IO. 



dd. Fore metatarsus is longer than its tibia. 



e. Thorax black with yellow humeri; petiole of 

 media about 6 times as long- as cell R^ ; length 

 4 to 6 mm. 5. simplex. 



ee. Thorax largely yellow. 



f. Subcostal crossvein is placed proximad or at 

 the middle of cell R^. 

 , g. Length 3.5 mm. "Both anterior and pos- 



terior margins of each tergite, pale." 



17. hirticollis. 

 gg. Length 4 to 5.5 mm. 



h. Fore metatarsus about 1-12 longer than 

 its tibia, 

 i. Subcostal crossvein is placed at mid- 

 dle of cell R^. 23. recurva n. sp. 

 ii. Subcostal crossvein proximad of 

 middle of this cell. 

 23. recurva var. chloratica n. var. 

 h. Fore metatarsus over 1-5 longer than 

 its tibia. 24. incompta n. sp. 



ff. Subcostal crossvein is distad of the middle of 

 the small cell R^ ; "apex of R2+3 turned to- 

 ward the base of wing" ; length 6 mm. ; 

 Colorado. 25. angulata. 



I. My corny a littoralis Say. 

 1824. littoralis. Say, Long's Exp. St. Peter's River. App. 361. 



{Sciophila). 

 Male. Length 3.5 mm. Vertex fuscous, ocellar spot, black, 

 eye margin and occiput sub fuscous to yellowish; face, palpi, 

 mouth parts and scape yellow ; the flagellum fuscous, except 

 sometimes i or 2 basal joints; third joint nearly twice as long 

 as wide; antennal hairs pale, setae of the head, black. Thorax 

 yellow, 3 dark brown stripes on mesonotum, the laterals abbre- 

 viated anteriorly, the middle one prolonged both anteriorly and 

 posteriorly ; anterior margin of scutellum and a spot on metano- 

 tum, brownish ; the 4 scutellar setae and the setge of the anterior 

 and lateral margins of the thorax, black; the smaller setse of 

 the dorsum, arranged in 3 rows of 2 lines each ,are also black, 

 but the finer hairs on the dorsum and 2 longer ones on the pos- 

 terior margin are pale yellow. Abdomen yellow, the dorsum 



