108 Psyche [June 



becoming confluent before apex; each stria with row of punctures; fine scattered 

 hairs on elytra. 



Body beneath black, everywhere with fine hairs; mesosternum posterior to 

 coxfe finely granular; disc of metastemum flat, shining, wath few punctures; sides 

 of metasternum divided into two triangular areas, the outer, anterior part opaque 

 and strongly punctate, the posterior part smooth and shining. 



Legs dark brown to black, tarsi reddish brown. 



Described from eight specimens from nest of Formica rufa subsp. 

 obscuripes, Pullman, Wash. 



The width of the sutural stripe is variable. In two of the speci- 

 mens before me the punctures of the striae are larger and brown, 

 and the striae appear as brown stripes. There is a perfect grada- 

 tion from this to the totally unstriped form. Structurally this 

 species can be assigned to none of Horn's groups of the genus. 



I have placed paratypes of A. suspedus in the collections of H. C. 

 Fall, H. F. Wickham, and E. C. Van Dyke. 



Hetaerius exiguus sp. nov. 



Shining, color light reddish to dark brown; form rather elongate. Head above 

 very faintly punctured, with few hairs; clypeus with stronger punctures; front 

 slightly concave. 



Prothorax transverse; sides straight, convergent from base to oblique trunca- 

 tion of outer angle; disc very minutely punctured; punctures without evident 

 hairs; no evident hairs on prothorax except short brush at margin; lateral portion 

 not more noticeably punctate than the disc, separated from rest of disc by shallow 

 groove, which terminates in depression at anterior and at posterior margin: divided 

 at basal third by shallow, oblique impression, the posterior portion slightly convex, 

 sUghtly elevated. 



Elytra at base a little ^ider than prothorax, marginal striae complete, discal 

 striae nearly attaining the apex of the elytra, hairs few, short and fine, stronger at 

 margins and toward apex, most of the disc not noticeably hairy. Prosternum mar- 

 gined for five eighths of the distance from base, the margined posterior of disc 

 impunctate and shining, anterior part coarsely punctured. 



Anterior femora about two sevenths as wide as long. 



Eleven specimens taken at Pullman, Wash., during April and 

 May 1910, with Formica sanguinea var. argent ata Wheeler, either 

 in independent nests or with Polyergus. One specimen, April 

 4 at Kendrick, Idaho, with the same species of ant. One at 

 Kendrick, Idaho, April 1, with Stenainma (Aphoenogaster) siib- 

 terranea var. occidentalis. This is the least hairy and most elongate 



