128 Trans. Acad. Sci. of St. Louis. 



with the medial joints less than twice as long as wide; lustre 

 polished 12 



12 — Form stouter; head well developed, fully as wide as long, the sides 

 parallel and straight, the angles broadly rounded; eyes well developed, 

 at less than twice their own length from the base, the punctures coarse, 

 moderately sparse, wanting at the middle of the vertex; prothorax 

 distinctly elongate, just visibly wider than the head, the sides par- 

 allel, nearly straight, the basal angles broadly rounded, the punctures 

 only moderately coarse but less sparse than usual; elytra longer than 

 wide, parallel, a fifth wider and barely a fourth longer than the pro - 

 thorax, the punctures fine, arranged in rather regular and feebly 

 impressed series almost throughout; abdomen distinctly narrower than 

 the elytra, minutely, not very closely punctulate and somewhat shining. 

 Male unknown; female with the sixth ventral conical, convex, rather 

 narrowly but obtusely rounded at tip. Length 6.8 mm.; width 1.18 

 mm. California (Yuma) atronitens n. sp. 



Form somewhat more slender and elongate; head very nearly as long as 

 wide, coarsely and sparsely punctate, the sides behind the eyes nearly 

 straight and just visibly converging to the broadly rounded basal 

 angles; eyes at one -half more than their own length from the base; 

 antennae rather thick, not quite as long as the head and prothorax, 

 the latter distinctly elongate, very slightly wider than the head, the 

 sides subparallel and nearly straight, broadly rounding toward base, 

 the punctures rather coarse, sparse, narrowly aggregated along the 

 median smooth area; elytra unusually elongate, parallel, fully a fourth 

 longer than wide, about a fourth or fifth wider and a third longer than 

 the prothorax, the punctures rather small but distinct, arranged in 

 regular and broadly impressed series nearly throughout; abdomen 

 obviously narrower than the elytra, minutely and rather sparsely 

 punctulate and shining, black above, the under surface feebly rufescent 

 throughout. Male unknown; female with the sixth ventral rather 

 broadly rounded at tip. Length 7.0 mm.; width 1.05 mm. Texas 

 (Galveston) galvestonica n. sp. 



The representatives of more distinct structural types, among 

 the species above described, are calif ornica, which stands 

 alone, jjolita and floridae, which form an isolated group, and 

 longiuscula and all the other species, which form a natural 

 aggregate, although, as may be inferred, there are marked 

 differences in coloration. The sexual characters oifallaciosa 

 are remarkably different from those of any other species, the 

 contrast between the very narrow deep ogival notch of the 

 sixth ventral in that species, and the large, broadly rounded 

 emargination of the same segment characterizing soror, for 

 example, being very remarkable. It is probable that the 

 Lathrobium serialum, of LeConte, previously referred to, 



