NO. 13 



STAPHYLINIDAE — BLACK WELDER 



53 



Pig. 12. — Intrafamily variation in the form and structure of 



the ventral aspect of the head. 



A, T any rhinus sing ularis Mann. B, Astenus discopunctatus (Say). C, Eumalus 



niqrella (Lee). D, Oxyporus lateralis Grav. E, Aploderus linearis Lee. h, 



Hypocyptiis longicornis (Payk.). G, Stenus sculptilis Csy. H Lathrini<ieum 



pictum' Fvl I, Metoponciis varians Shp. J, Philonthns alumnus Lr. 



