164 Trans. Acad. Set. of St. Louis. 



two groups cannot be considered a generic character in any 

 sense.* The species are readily distinguishable among them- 

 selves, as a rule, by structural peculiarities relating to the 

 intermesocoxal parts, sculpture, antennal characters, length 

 of the basal joint of the hind tarsi and other easily observed 

 features. 



Verna has been inscribed in our lists under the name 

 nitida Grav., but is by no means identical, having longer and 

 more closely punctured elytra and more finely and cloaely 

 sculptured abdomen ; it is given in the European catalogue as 

 a species different from nitida, but I have seen no European 

 representatives. It varies noticeably, not only in size but to 

 some extent in development of the elytra and density of 

 sculpture, as might be inferred from its very extended range, 

 although bimacidata, which is even more widely distributed, 

 is notably less plastic. The southern California innocua 

 closely approaches bimacidata Grav., in general structure, 

 but is rather less stout, having also obviously shorter and paler 

 elytra and a smaller, more parallel prothorax. The male of 

 ohsolescens possesses one character which, as far as known to 

 me, is unique in the subtribe, the sixth ventral plate having 

 at tip a small, abruptly incised and acutely angulate cleft. 



* Ti'is species may be described as fallows: — 

 Form moderately stout, parallel, convex, shlniug, deep black, the elytra 

 scarcely visibly picesceut, not detinileiy maculate, the lejis acd auttinuae 

 black; head fully ihree-flflhs as wide as the prothorax, finely, reuiotely 

 puiictate, tut) ariteuDae barely (viu^-balf longer than the head, strouyly 

 incra.SMate imd compact disialiv, the secoud joint much longer thau the 

 the third aad almost as loug a.s the next two comnined; prothorax 

 nearly oue-half wider thau long, slightly uairower from bif-e lo apex, 

 with the sides evenly and strongly arcuate, the base arcuate, the 

 angles obtusely rounded, the punctures very sparse, disposed as in 

 verna throughout; elytra scarcely at all wider than the prothorax and 

 about as long, the suture not quite as long as the median line, the 

 punctures and pubescence as in vernn; abdomen parallel, nearly as 

 wide a-i the elytra, finely, rather sparsely punctured throughout, the 

 punctures of the impressions not larger; rneM;sternal proce.-s narrow, 

 the carina very much abbreviated, not extending quite to the middle 

 of the acetabula; hiud tarsi as long as the tibiae, tiie basal joint fully 

 as long as the filth and as long as the next two together. Length 

 2.7 ram.; width 0.83 mm. Mexico (Federal District) .-coinposita n. sp. 



