NEW NORTH AMERICAN PSELAPHID^. 455 



ON SOME NEW NORTH AMERICAN PSELAPHIDiE. 



(With Plate XVI.) 



BY THOS. L. CASEY. 



Read July 18th, 1887. 



The Pselapliide fauna of the Pacific coast is by no means 

 so insignificant as it has hitherto been considered, and as 

 the search for these singular and fascinating forms becomes 

 more specialized, and their habits and localities better 

 known, new species are discovered in abundance. 



For those w^ho would prosecute a more extended collec- 

 tion of these insects, it may be stated that the Californian 

 Pselaphidae are very seldom found with ants, although a few 

 myrmecophilous species are known, but generally in fun- 

 gous earth, about the roots of trees, under bark, or in the 

 long wet moss covering the rocks in the secluded ravines of 

 mountainous regions. The genus Oropus, and several spe- 

 cies of Eeichenbachia and Batrisus are peculiar to the last- 

 named localities, while Euplectus and. Pytna are always 

 found under bark. Sonoma and Actium are sometimes 

 found under bark, but often also in fungous earth. Batri- 

 sus zephyrinus, on the other hand, I found in abundance at 

 Lake Tahoe, living in the most indiscriminate localities — 

 under bark, under chips buried in grassy turf, and in 

 fungous earth. 



The following forms, most of which were collected by 

 myself, and which have been- accumulating in my cabinet 

 during the past two years, are here described as new, al- 

 though it is possible that Actium californicum Lee, may be 

 redescribed under that genus. This can only be the case, 

 however, under the supposition that the description given 

 by LeConte for that, species is erroneous in regard to the 



32— Bull. Cal. Acad. Sci. II. 8. Issued August 2, 1887. 



