1912] Fall — Myrmecophilous Coleoptera 11 



with the description of myops Csy., but that species is smaller 

 and less elongate according to measurements given (length 1.35 

 mm, ; width .6 mm.) the prothorax scarcely longer than wide, the 

 transverse basal impression of the latter deeper than in gracilis 

 and the color quite different. 



I am not aware that beetles of this genus have been found with 

 ants and it is possible that the association was in this case acci- 

 dental; the small eyes and obsolete humeri may be significant and 

 indicative of a more subterranean life. 



Of the other species of this interesting genus, biformis Makl. 

 occurs in Alaska (Queen Charlotte and Prince of Wales Islands), 

 arcifer Csy,, described from Astoria, Oregon, was found by Mr. 

 H. S. Barber at Eureka in Northern California; gracilis is not 

 rare about San Francisco Bay; myops is described from San Fran- 

 cisco, 



Batrisodes aphaenogastri sp. no v. 



Red brown, polished, subimpunctate, sparsely finely pubescent. Closely in 

 agreement in all general features and most details with the other members of 

 the group to which it belongs. By Casey's table — Annals N. Y. Acad. Sci. VII, 

 1893, p. 469 — ^it falls with albionicus and zephyrinus, being most nearly allied to 

 the former, from which it is separable with certainty only by the pygidial char- 

 acters of the female. In the male the pygidium is broadly evenly convex, in the 

 female rather strongly tumid posteriorly as a whole, and with a small basal con- 

 ical tubercle. The two small median prominencies at the base of the first dorsal 

 segment of the abdomen are not appreciably produced backward as carinse, and 

 are mutually nearer together than either is to the inner line of the side margin. 

 The median pronotal sulcus is feebly impressed, but detectable in basal half. 

 Length 2.5 mm.; width .8 mm. 



Kendrick, Idaho, 



Described from one pair taken by Prof. A. L. Melander, in 

 nests of Aphcenog aster subterranea var. occidentalis, and sent me by 

 Mr, Mann, 



Xenomedon gen. no v. (Staphylinidae). 



Body rather broad and somewhat depressed, integmnents densely punctuate and 

 dull. Head subquadrate, eyes small; labrum quadridentate, the teeth acute, very 

 nearly equal in prominence, the two middle ones a little more distant; gular sutures 

 rather widely separated, most approximate before the middle; third joint of max- 

 illary palpi oval, not quite twice as long as wide, apex broadly squarely truncate. 

 Antennae moderate, not appreciably wider distally, joints 1-10 feebly obconical, 

 the first about twice as long as wide, wider than and subequal in length to the two 



