360 APPENDIX. 



Head and thorax blackish -brown ; antennx, palpi, 

 mouth, and hypostoma, except near the base of the an- 

 tennae, whitish ; wings with four, brown, subequidistant 

 bands, of which the third reaches the inner margin and the 

 others are abbreviated ; pleura, pectus, and /ee^, 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 Ocv- 

 PETE. It occurred in June. 



TRICHOCERA, Meig. 



T. scutellata. Dark fuscous ; scutel whitish. 



Inhabits North-west Territory. 



Palpi, blackish j thorax slightly tinged with livid ; an- 

 terior angles and neck segments dull yellowish-piceous ; 

 scutel dull whitish ; wings immaculate, whitish at base ; 

 poisers white, with a fuscous capitulum ; coxse, and thighs 

 at base, dull yellowish. 



% 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 yellowish-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 black- 

 ish subterminal band. 



Inhabits North-west Territory. 



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

 maculate ; wings hyaline, with a blackish band near the 



