348 



PUPAE 



1. Antennal sheath with a thorn at base lugens. 



— Antennal sheath without a thorn at base ahdominalis. 



IMAGINES 



1. Legs entirely black, at most the apices of the coxae yellow^ ; basal an- 



tennal joint much elongated (Mass.) longicornis Loew. 



— Legs with a considerable proportion or all of fem.ora and tibiae red- 



dish or yellowish 2 



2. Abdomen largely reddish 3 



— Abdomen black or blackish brown 4 



3. Abdomen ferruginous, sutures and lateral margins of segments 



black ; legs tawny, tibiae and tarsi brownish and darker than the 

 femora (Martin's Falls and Montreal, Canada) . .fasciaius Walker. 

 — • Abdomen black, broadly reddish on disc of segments 2 to 5 ; legs red- 

 dish, apical 2 joints of all tarsi blackened (Texas, N. J.) 



ahdominalis Loew. 



4. Hind legs almost entirely black, only the extreme bases of femora 



and tibiae and the larger basal portion of metatarsi whitish yel- 

 low (111., N. Y., N. J., Pa., N. H.) lugens Loew, 9 . 



— Hind legs with a greater proportion of their surfaces yellowish or 



whitish 5 



5. Legs reddish or tawny, only apices of tarsi blackened 6 



— Legs with some portion of femora or tibiae blackened or browned. .7 



6. Antennae not longer than head, entirely black; proboscis 



C' mouth", Walker) yellow (N. Y.) ." . .reflectens Walker. 



— Antennae longer than head, tip of first joint and second reddish 



brown; proboscis black (Wash. State) decorus Williston. 



7. Legs reddish, apical third of hind tibiae and apices of tarsi black- 



ened (Mass.; Montreal, Can.; White Mts., N. H. ; N. J.; Axton, 

 N. Y.) (persequus Walker) rufipcs Loew, 



— Legs yellowish testaceous or j)alc yellow, femora blackened or dis- 



tinctly browned at apices 8 



8. Legs yellowish testaceous, all femora broadly sulfurou.^ apically, 



tips of fore and mid tibiae, hind tibiae except bases, and all tarsi 

 except bases of metatarsi blackened lugens Loew, S . 



— Legs pale yellow, apices of all femora, tips of hind tibiae and of all 



tarsi light brown (Wash., Oregon) gracilis Williston. 



As this key is largely compiled from descriptions it will be neces- 

 sary to use it with considerable caution. I am not entirely convinced 

 of the specific distinction of several of the species, but without examin- 

 ing the types it is not possible to find characters for the separation 

 other than those given here. Say's species triangularis is not, I am 

 convinced, a Xylophagiis. 



