FUNGUS GNATS OF NORTH AMERICA. IO3 



near the base, apex of each hind femur black; middle tibiae each 

 with 2 or 3 set£e on flexor surface; tibial spurs whitish dis- 

 tinctly tipped with black; tarsi dusky; hind metatarsus about 

 as long as the 3 following joints taken together. Wing with 

 central spot with a preapical fascia formed of 3 fuscous spots 

 arranged like the letter S, the first and largest extends from 

 the apex of cell Rt to vein Ml "Middle States." 



There are 2 ranges of setae on the extensor surface of the 

 hind tibiae in the type specimen. 



35. Mycetophila fatua n. sp. 



Male. Length 4.5 mm. Head and antennae brown, the scape, 

 palpi and very base of flagellum yellow. Thorax dull yellow- 

 ish, mesonotum with 3 subconfluent dull dark brown vittae, 

 pleura, metanotum and sides of scutellum brown, setae black 

 Abdomen dark brown, the intermediate segments with yellow 

 hind margins; hypopygium (Fig. 87). Coxae and legs yellow- 

 ish, the central portion of the coxae, flexor surface of the 

 femora near the base, tips of hind femora and of tibiae and the 

 apical part of the tarsi, brown, fore metatarsus about 7-8 as 

 long as the tibia; middle tibiae each with 2 setae on flexor sur- 

 face ; hind tibiae each with 2 ranges on extensor surface ; hind 

 metatarsus 7-8 as long as the 4 remaining joints. Wings gray- 

 ish hyaline, costal cell yellowish; with central spot, a large 

 brown preapical more or less interrupted fascia, a faint cloud 

 at apex of the wing and another behind the fork of the cubitus 

 (Fig. 206). Halteres yellow. Moscow, Idaho (J.M.A.). 



Female. Similar, but thorax a little paler brown, and the 

 preapical wing fascia more broadly interrupted in cell Mt. 

 Vollmer, Idaho. 



36. Mycetophila cdura n. sp. 

 Male. Length 2.5 mm. Head and antennae grayish brown, 

 the palpi, scape and base of flagellum yellow. Thorax and 

 abdomen dark brown, subopaque, the humeri and the narrow 

 posterior angles of the mesonotum yellow, hairs yellow, setae 

 black; hypopygium (Fig. 88). Coxae and legs yellow, the ex- 

 tensor surface of the hind femora and the tarsi brownish; fore 

 metatarsus about .8 of tibia in length, middle tibiae each with 

 2 setae on flexor surface, hind tibiae each with 2 ranges of seta?; 

 on extensor surface, hind metatarsus about 1-16 shorter than 



