EROTYLID^E 151 



in Colorado by Levette, which answers much better to the de- 

 scription of that species, I conclude that it is not divisa but widely 

 distinct because of antennal structure. My single specimen of 

 divisa has the black basal fascia of the pronotum entire from side 

 to side but only occupies basal third of the length, with its anterior 

 limit transverse and only feebly undulated; the antennal club has 

 its basal joint, the seventh, not distinctly wider than long and very 

 much narrower than the next joint, while in thoracina it is broad, 

 twice as wide as the sixth and as wide as the eighth; this is a 

 very striking difference. The structure of the antennae was not 

 alluded to by Dr. Horn in describing divisa, which is said to occur 

 in Colorado and New Mexico. 



*Acropteroxys aztecana n. sp. Form slender, convex, shining, the 

 pronotum sometimes very feebly alutaceous; color deep black, the elytra 

 with feeble bronzy lustre; head, antennae and legs black throughout; 

 prothorax ferruginous, the upper surface black throughout basally, 

 the black area prolonged anteriorly, gradually diminishing in width, to the 

 apex, in the greatest development of the black area leaving only a large 

 rufous spot at each side anteriorly; beneath, the surface, together with 

 the coxae, is rufous, becoming broadly black laterally except toward apex; 

 head finely and sparsely but deeply punctate, the 5-jointed antennal club 

 rather narrowly fusiform, the seventh joint scarcely wider than long, 

 similar to the eighth in outline but a little smaller; prothorax between a 

 fourth and third longer than wide, parallel, barely at all arcuate at the 

 sides, the basal angles feebly prominent; base bisinuate; surface remotely 

 and very minutely punctulate, the strioles minute, the basal sulcus not 

 attaining the sides; scutellum smooth, broadly angulate at apex; elytra 

 fully four times as long as wide, at the broadly rounded humeri much 

 wider than the prothorax, the straight sides thence just visibly con- 

 verging, gradually more so and broadly arcuate posteriorly, to the narrow 

 apex, the tips dehiscent, each very narrowly blunt; punctures moderate 

 in size, deep, rather close-set in even and unimpressed series, gradually 

 very minute posteriorly and wholly disappearing for a considerable 

 distance before the tips; sutural stria impressed as usual except behind 

 the scutellum, having near the apices a short dilatation; last ventral rather 

 closely punctate except at base. Length 7.3-9.5 mm. ; width 1 .2-1 .6 mm. 

 Mexico (Puente de Ixtla, Morelos), Wickham. 



This species seems to be figured by Gorham on plate I, fig. 19, of 

 the "Biologia," as a variety of gracilis, but it is not closely related, as 

 in gracilis the entire prothorax above and beneath, excepting a 

 regular entire median dorsal vitta, is ferruginous, and the seventh 

 antennal joint is very much more markedly smaller and narrower 

 than the eighth ; the transverse basal impressed line of the pronotum 



