332 CASEY 



ing the basal joint of the hind tarsi much longer than the fourth 



and the base of the prothorax lobed in the middle. It is a 



composite genus and may be resolved into the three following 



subgeneric groups : — 



Mandibles subhorizontal, feebly toothed on the upper surface, the right 

 tooth slightly the more developed, as usual, and feebly clasping the 

 labrum ; frontal margin varying from broadlv and feebly arcuate 

 to sinuato-truncate ; mentum transverse, broadly rounded at apex, 

 with a small broadly sinuate apical emargination ; body very 

 narrow and elongate as a rule, the sculpture usually rather coarse : 

 metasternum but slightly longer than the first ventral... Hylocrinus 



Mandibles shorter, stouter and more deflexed, convex above but not 

 toothed, folding wholly beneath the labrum ; body broader in 

 form; metasternum much longer than the first ventral 2 



2 — Mentum less transverse than in Hylocrinus^ biobliquely rectilinear 

 at apex, the apical angle abruptly and sinuously emarginate ; 

 frontal margin feebly biemarginate, the epistoma generally some- 

 what advanced and always broadly sinuate Locrodes 



Mentum shorter, transverse, the apex broadly arcuate, without trace of 

 the small emargination so constant elsewhere in the tribe ; frontal 

 margin arcuate, not biemarginate, somewhat narrowly sinuate at 

 the middle Paravius 



The hind wings appear to be fully developed in the last two 



of these groups but not in the first, the metasternum being 



decidedly longer than the first ventral segment in the former 



but not so distinctly in the latter. The species may be described 



as follows : — 



Hylocrinus in sp. 



Frontal margin perfectly even throughout, without trace of minute 

 emarginations at the ends of the oblique sutures 2 



Frontal margin broadly, feebly sinuato-truncate, sometimes biemar- 

 ginate 6 



2 — Frontal margin broadly, feebly arcuate; species confined to 



southern California and w^estern Arizona; body very elongate, 



narrow and moderately convex 3 



Frontal margin transversely rectilinear; body less elongate; species 

 more eastern in range 5 



3 — Punctures of the pronotum strong throughout, becoming very 



gradually dense, coalescent and forming long parallel ruga; toward 

 the sides, moderately close toward the middle. Body parallel, 

 only moderately convex, shining, piccous-black, the under surface, 

 legs and clytral suture more or less rufous ; head rather closely 

 and strongly punctin-ed, the sides rather feebly converging, strongly 

 arcuate, merging into the median parts through very broadly 



