26 COLEOPTERA OP NORTH AMERICA. 



stria, one-fourth from base and one-fourth from apex. Prosternum 

 not prolonged. Mesosternum nearly flat, the middle coxae dis- 

 tant, epimera wide nearly equalling the episterna. Metasternal 

 epimera distinct, posterior coxae contiguous. Ventral segments 

 3-4-5 with posterior margins coriaceous. Legs moderate, the 

 tibiae smooth externally, the anterior emarginate with the spurs 

 distant. 



Tbe anterior tarsi do not differ in the sexes ; the sexual cha- 

 racters are the same as in Scarites. 



The only genus known which can be referred to this tribe is 

 Paydrus. Its form is not unlike some Bembidia, the color piceous. 



One species of Paydrus is known {P. piceus Lee), which 

 occurs from Lake Superior to northern California. It lives 

 under dead bark, and ejects a liquid from its anus when disturbed, 

 which is not, as in Nomius, especially offensive. 



Tribe XV.— MORIOiVIi\I. 



Antennae more or less moniliform with four entirely glabrous 

 joints, arising under slight frontal plates. Head suddenly nar- 

 rowed behind the eyes, neck stout, front with two supra-orbital 

 setae, clypeus slightly prolonged. Eyes round, moderately promi- 

 nent, truncate posteriorly by the sides of the head, distant beneath 

 from the buccal opening. Mandibles at least slightly prominent, 

 without setigerous puncture externally. Maxillae ciliate inter- 

 nally (with a tooth behind the apex in Morio); the palpi mode- 

 rate, the last joint slightly fusiform. Mentum deeply emarginate, 

 usually with a bifid tooth; ligula broad, free and bisetose at apex, 

 the paraglossas slender, longer than it, not ciliate; palpi mode- 

 rate, the last joint cylindrical (longer than that of the maxillary 

 Morio). Thorax with a setigerous puncture at each angle (and 

 three at the side Morio). Body slightly pedunculate, scutellum 

 distinct. Elytra feebly margined at base, sides narrowly inflexed, 

 disk with a single dorsal puncture at apical third, on the third 

 interval near the third stria ; margin with a very feeble interrup- 

 tion but with a distinct internal plica. Prosternum not pro- 

 longed. Mesosternum rounded in front, the epimera very narrow. 

 Metasternal side pieces narrow, the epimera distinct, posterior 

 coxae contiguous. Ventral segments without coriaceous margin. 

 Tibias gradually broader to apex, the middle finely spinulose 



