Horn. 



OPimYASTLNTI. 31 



and the vittate elytra It varies greatly in form primarily from sexual 

 differences. 

 Occurs in Kansas and New Mexico. Not rare 



O. tuberosus Lee. Proc Acad, vi, p. 443. 



Rostrum trisulcate, sulci rather broad and shallow, median passing 

 slightly on the front, lateral extending above the eyes, transverse impres 

 sion at base of rostrum feeble. Thorax nearly twice as wide as long, con- 

 stricted at apex and base, sides (tubei'osities) slightly divergent and notched 

 at middle, surface deeply punctured and very irregular. Elytra regularly 

 oval with rows of large, deeply impressed punctures ; surface densely 

 covered with cinereous scales and maculate with black. Body beneath and 

 legs densely covered with whitish scales, femora with black spots near the 

 tip. Length .40-. 50 inch ; 10-12 mm. 



This species occurs rather abundantly in Colorado and New Mexico. 



O. latirostris Lee, Proc. Acad, vi, p. 443; validus 9 Lee, Proc. Acad, 

 vii, p. 225. 



Rostrum deeply transversely impressed at base (front convex) trisulcate, 

 lateral sulci moderately deep, median sulcus broad, shallow, neither ex- 

 tending beyond the transverse impression. Thorax nearly twice as wide 

 as long, anteriorly moderately at base suddenly and strongly constricted, 

 sides divergent from apex feebly notched at middle ; surface deeply punc- 

 tured and very irregular. Elytra regularly oval, feebly (^ or not 9 striate 

 with moderately impressed punctures. Body beneath and legs densely 

 covered witli whitish scales. Length .44-.64 inch ; 11-16 mm. 



The elytra are densely covered with cinereous scales, and with small 

 irregularlj^ interspersed fuscous spots, but to a much less extent than in 

 the preceding species. From both the preceding species the present differs 

 in the convex front, the rather deep transverse impression of the base of 

 the rostrum as well as the form of the grooves. The thorax does not differ 

 greatly in form in the three species, but is much less collared in this than 

 in tuberosus. The median line is impressed in some and obliterated in 

 other specimens. 



Occurs in Kansas, New Mexico and Utah. 



O. sulcirostris Say, (Lipanis) Journ. Acad, iii, 1824, p. 316 ; Gyll. 

 Sch.Gen. Cure, i, p. 509; Lee, Proc. Acad, vi, p. 443; ligatus Lee, loc. 

 cit 



Rostrum deeply transversely impressed at base, median sulcus moderate, 

 lateral sulci short. Front convex. Thorax one-third wider than long, at 

 apex moderately, at base strongly constricted, sides divergent from apex 

 moderately tuberose, thorax deeply punctured and irregular. Elytra oval, 

 humeri oblique, surface not or only obsoletely striate and with rows of 

 inoderate punctures, intervals feebly conxex ; surface densely covered with 

 pale cinereous scales maculate with fuscous, sometimes entirely plumbeous. 

 Body beneath and legs densely covered with white or plumbeous scales 

 Length .32-36 inch, 8-9 mm. 



