APPENDIX. 347 



small spot on the front, another in each emargination of 

 the eyes, and a transverse one behind the eyes on each 

 side, yellow ; thorax densely punctured, a yellow spot on 

 each side of the collar ; wing-scale yellow, with a pale- 

 brown spot ; wings fuliginous ; scutel with a transverse, 

 yellow line ; metathorax, on each lateral margin with an 

 oblique, yellow line ; pleura, a yellow spot under the su- 

 perior wing ; feet yellow ; thighs except at the knees, and 

 spot on the anterior tibiae, black ; tergum, segments yellow 

 on their posterior margins, first and second segments with 

 each a yellow, lateral spot, the former segment short, di- 

 lated, not pedunculiform ; venter immaculate. 



Length more than seven-twentieths of an inch. 



Excepting in the character drawn from the first segment 

 of the abdomen, this insect has a general similarity to the 

 preceding species, and the form of the anterior portion of 

 the hypostoma and the trophi, prove that this species is 

 properly placed in this genus. 



PTEROCHILUS, Klug. 



P. 5-fasciatus. Segments of the tergum yellow on their 

 posterior margins ; first and second segments with a late- 

 ral, ferruginous spot on each. 



Inhabits North-west Territory and Missouri. 



9 Head black ; dilated posterior orbits, and anterior or- 

 bits to the emargination of the eyes, ferruginous ; hypos- 

 toma, scapusoi the antennae and mandibles, ferruginous ; 

 tip of the former acutely emarginate in the middle ; Jla- 

 gellum black-brown ; labial palpi testaceous, very long, 

 ciliate with long hairs, three-jointed ; terminal joint much 

 compressed, flat, obtuse at tip ; stethidium black ; collar 

 and ^fm^-5ca/e ferruginous ; 5a</e/ with two, large, yellow 



