SHORT-WrNGED SCAVENGER-BEETLES. 75 



under-, and Icuptos — bent, iu allusion to their habit of bending the head 

 under the body, which, together with their convex form, gives them the 

 appearance of little globes or balls, much like the genus Agathidium 

 referred to above in the family Anisotomida, and also like Gyrophrena 

 in the preceding sub-family of Aleocharides, but in the last the effect is 

 produced in a different manner. The genus Coproporus, Kraatz, does 

 not seem to be sufficiently distinct from Tachyporus, nor Byroporus 

 from Boletobius, to render the formation of these genera necessary. 



Sub-family OMALUDES. 



Founded upon the genus Omalium, Grav., from the Greek omalos — 

 level, on account of the comparatively broad and depressed torm of most 

 of the species. Their most essential character is the presence of two 

 ocelli, resembling minute glass beads, on the back part of their heads — 

 a character peculiar to this sub-family, with but two or three known ex- 

 ceptions. But their most conspicuous character is the comparatively 

 greater length of the elytra, which also has a few exceptions. The large 

 depressed elytra give to some of these insects an obvious resemblance 

 to the Nitidulpe, in the preceding tribe ; but in these only the tip of the 

 abdomen is usually exposed, and their knobbed antennoe at once distin- 

 guish them from any of the Staphylinidse. The species of the present 

 sub-family are of obscure brown or yellowish colors, and small size, 

 never attaining a quarter of an inch in length, and often being less than 

 an eighth. Their habits are various, some being found in wet places, 

 under stones, or under decayed bark, whilst others are found on plants 

 and flowers, and Mr. Walsh bred some of them from fungi. 



Upwards of fifty N. A. species have been described, most of which are 

 contained in the following genera : 



A. Mandibles toothed ; head entirely free ; thorax heart-shaped, narrow beliind. 



B. Last joint of palpi three times as long as the preceding Lesteva. 



BB. Last joint of palpi not elongated Anthofhagus. 



A A. Mandibles simple; head partly inserted ; thorax not narrowed behind. 



C. Hind tarsi moderately elongated ; elytra covering the greater part of the abdomen ; tibiB not 



spinous Olophrum. 



C C. Hind tarsi short, the four first joints combined not longer than the fifth. 



D. Tibiae finally spinous ; elytra covering about half of abdomen Omalium. 



D D. Tibiffi not spinous ; elytra almost or quite covering abdomen Anthobium. 



AntJiophagus, Grav., scarcely differs generically from Lesteva, Latr. ; 

 but their habits are different— the former being found on flowers, and 

 the latter amongst wet herbage, near the water. They are easily dis- 

 tinguished from all other Staphylinidfe by the heart-shaped thorax, 

 which, together with the free head and prominent eyes, gives them a 

 remarkable resemblance to some of the smaller Carabidte. There is a 

 small yellowish species in the Walsh cabinet, labeled ^^Anthohium pro- 

 tectum, LeC, from Mass.," in which the abdomen is completely covered 

 by the elytra. 



