302 GEO. H. HORN, M. D. 



Male. — Last ventral distinctly sinuate each side, the middle lobe moderately 

 prominent, slightly concave and with a broadly triangular impression. Antennae 

 with joints 2-10 scarcely different in length, eleventh a little longer. 



Female. — Last ventral with a very faint impression near the apex. Antennse 

 as in the male. 



Among the species with simple antennae and non-vittate elytra 

 two have the elytral punctuation composed of equal punctures, the 

 present species and pusilla. The latter is smaller, more depressed, 

 the surface distinctly brassy, the thorax small and the punctuation 

 closer. 



Specimens occur with scarcely any bluish surface lustre, and those 

 from Nevada have the first five joints of the antennae more con- 

 spicuously pale. 



Occurs in Colorado, Illinois (Crotch), Texas, Nevada and ad- 

 jacent regions of California. 



15. P. pusilla n. sp. — Form narrow, elongate, depressed, piceous, surface 

 with distinct jeueous lustre. Antennae slender, half as long as the body, piceous, 

 joints 2-3 paler. Head scarcely visibly punctate. Thorax less than twice as 

 wide as long, widest at middle, sides arcuate, apex slightly narrower than base, 

 disc convex, surface shining, the punctures moderate, closely placed, but not 

 convex. Elytra wider than the thorax, humeri obtuse, punctuation coarser than 

 that of the thorax, closely placed, very little finer near the apex, but less dense, 

 surface shining. Body beneath and legs piceous, abdomen sparsely punctate. 

 Length .06— .08 inch. ; 1.5—2 ram. 



Male. — Last ventral with a feeble triangular impression in the apex. 

 Female. — Last ventral simple. 



The antenna? are alike in the sexes. The joints 8-10 vary but 

 little in length, although very slightly broader externally. 



This species could only be confounded with alhionica, which it re- 

 sembles in form, size and color. It is, however, more shining, the 

 head nearly smooth, thorax and elytra less densely punctured, the 

 latter never scabrous. 



Occurs from Dakota to Texas, Arizona, southern California and 

 Nevada. 



16. P. picta Say. — Oval, slightly oblong, feebly convex ; head, thorax and 

 legs pale reddish yellow ; abdomen piceous, elytra bright bluish green, surface 

 shining. Antennae a little longer than half the body, slightly thicker exter- 

 nally, basal joints pale, outer joints fuscous. Head smooth, frontal carina and 

 tubercles distinct, a vague longitudinal impression of the vertex. Thorax nearly 

 twice as wide as long, distinctly narrowed in front, sides arcuate, slightly ob- 

 liquely truncate at the front angles, disc moderately convex, the punctuation 

 very fine, sparse and indistinct. Elytra a little wider at base than the thorax, 

 humeri rounded, umbone smooth, not brownish, surface moderately closely, 



