244 long's second expedition. 



blackish ; incisures edged with whitish ; thighs with a very ob- 

 vious blackish tip. 



Length to tip of the wing 9 seven-tenths of an inch. 



PTYCHOPTERA Meig. 



P. 4-FASCiATA. — Wings hyaline, with four brown bands. 



Inhabits Pennsylvania. [365] 



Head and thorax blackish-brown ; antennae, palpi, mouth, and 

 hypostoma, except near the base of the antennss, whitish ; wings 

 with four brown, subequidistant bands, of which the third 

 reaches the inner margin and the others are abbreviated ; pleura, 

 pectus, and feet, yellowish white; the incisures of the latter 

 dusky. 



Length to the tip of the wings nearly half an inch. 



This species is infested by a parasite of the genus Ocypete, 

 It occurred in June. 



TRICHOCERA Meig. 



T. scuTELLATA. — Dark fuscous; scutel whitish. 



Inhabits North-west Territory. 



Palpi blackish ; thorax slightly tinged with livid ; anterior 

 angles and neck segments dull yellowish-piceous ; scutel dull 

 whitish ; wings immaculate, whitish at base ; poisers white, with 

 a fuscous capitulum ; coxae, and thighs at base, dull yellowish. 

 Z 9 Length of the body three-twentieths of an inch. 



Taken in September at the Falls of Kakabikka, beyond Lake 

 Superior. The posterior margin only of the scutel is dull yel- 

 lowish-white in the male. This species seems to be closely allied 

 to T. parva Meig. 



PLATYURA Meig. 

 Ceroplatus Bosc, Fabr. 



P. fascipennis. — Thorax yellowish; wings with a blackish 

 subterminal band. 



Inhabits North-west Territory. 



Head yellowish ; disk of the vertex black ; thorax immacu- 

 late ; wings hyaline, with a blackish band near the [ 361 ] tip, 

 hardly reaching the inner edge, and margined with an obsoletely 

 whiter color than the other parts of the wing; poisers color of 

 the thorax ; coxae and thighs whitish ; tergum blackish-testace- 



