NORTH OF MEXICO. 



313 



E. nigrina, Leo., Proc. Acad. 1858, p. 180. 



With this species commences a series in which the humeral singles of the elytra are 

 much more distinct than in. the two preceding. The thorax is also much less convex. 

 From the species following, this one may be readily known by the femora being merely 

 feebly sinuate in both sexes. The elytra are feebly striate, with muricate punctures not 

 very densely but very irregularly placed. The males are rather more slender than the 

 females. The elytra of both arc sub-opaque, a character otherwise unknown in the group. 

 More decidedly Upiform than any other species. 



Occurs in Oregon, thence eastward to Dacota, and southward into Colorado and 

 western Kansas. 



Length .60— .86 inch. 



E. hispilabris, Say, (Blaps) Journ. Acad. 8, 360; Am. Ent. pi. 16. sulcata || Lee, Proc. Acad. 0, 07; eon- 

 vexa, Leo., Paoif. R. R. Repts., App. 1, p. 40; nupta, Leo., Proc. Aoad. 1858, p. 188. 



I have no hesitation in applying the name of Say to one of our species, better known 

 under the pre-occupied designation sulcata, Lee. The description and figure of Say ap- 

 pear to me perfectly applicable to this and not to one of the larger species of Group I. 

 The prominent dentiform anterior thoracic angles, so well described and figured, are not 

 found in any species of the ohscnra series. I am unable to find characters warranting the 

 division of the species into three; others, the forms so completely passing from one to the 

 other without a break in the series. The species may be readily distinguished from all 

 those having the same form of thorax, by the more or less deeply snlcate elytra, with con- 

 vex interstices. The strise are punctured and the interstices smooth. In the variety 

 nupta, the elytra are rather more convex and broader, and the sulci less deep, and the 

 interstices consequently much less convex. 



Occurs abundantly in Oregon and Arizona, Kansas, Colorado and Texas. Say's spe- 

 cimens came from " Missouri," a very badly defined geographical region in his day. 



Length .70-1.05 inch. 



E. sponsa, Lee, Proc. Acad. IH58, p. 181. 



In general form this species resembles the preceding. The thorax is, however, less 

 rounded on the sides and more nearly quadrate. The anterior angles arc acute and fre- 

 quently prominent. The elytra are elongate oval, slightly flattened, feebly sub-striatc 

 and with the interstices rather coarsely muricately punctured. The apex is moderately 

 acute in the male, never prolonged or caudate. The anterior femora of the males are fur- 

 nished with an acute tooth, the females with one more obtuse. 



Occurs in southern Colorado and eastern New Mexico. 



Length .80-96 inch. 



AMBRI. PHILOSO. SOC. — VOL. XIV 19 



