444 [December, 



profundissimo, lateralibus rectis profundis, mox ante oculos abbreviatis, thorace 

 lalitudine plus duplo breviore inaequali, parce profunde punctate, lateribus sub- 

 bituberosis, canaliculate saepe fusco trivittato, elytris striis vix impressis pro- 

 funde punctatis, sutura cuprascente, fusca-interstitiis 3, 5 et 7mo fusco-vittatis. 

 Long. -41 48. 



Schonherr, Cure. 1, 509 ; 5, 819. 



Lipartis vittattts Say, Journ. Acad. Nat. Sc. 3, 316. 



Platte and Arkansas Rivers ; not rare ; found also by the Commission at Eagle 

 Pass. The elytra of the male are but little wider than the thorax, those of the 

 female are more rounded, a little flattened on the back, and about one half wider 

 than the thorax ; the dark vittae of the thorax and elytra appear to be produced, 

 in part, by abrasion, as specimens occur in which they are hardly to be seen. 

 The suture, as far as the first stria, is covered with brown scales, having a slight 

 coppery reflexion. 



B. Thorax lateribus late regulariter rotundatis. 



6. O. s p e c i o s u s, niger supra cupreo-fusco-squamosus, capite albo-squa- 

 moso vitta frontali alteraque pone oculos utrinque fuscis, rostro 5-sulcato, sulcis 

 intermediis brevibus baud profundis, thorace latitudine breviore lateribus rotun- 

 dato parce subtiliter punctato, subtiliter canaliculato, vitta utrinque dorsali 

 alteraque in latere niveis, elytris elongato-ellipticis striis profundis punctatis, 

 interstitiis vix convexis, parce punctulatis, 2, 4, 7mo niveis, lateribus et subtus 

 albo-squamosus. Long. '8. 



Eagle Pass, several specimens. This fine species is certainly the most beau- 

 tiful of this family yet found in the United States : the lateral grooves of the 

 rostrum are situated in the side and converge a little posteriorly ; the inter- 

 mediate grooves occupy the position of the lateral grooves in the species of 

 division (A.) and are very short, not by any means obvious ; the vittae of the 

 thorax are made up of spots placed close together and separated by narrow lines; 

 two or three small spots are scattered between the dorsal vitta and the lateral 

 one ; the anterior and posterior constriction, with their rows of punctures areas 

 in the species of the first division, but are hardly apparent in the lateral outline 

 of the thorax, which is regularly curved, only a little indented at base and apex ; 

 the elytra of the male are about one-fourth, those of the female about one-third 

 wider than the thorax ; the snowy white vittae are a little irregular in their out- 

 line, the elytra beyond the 7th stria are covered with grayish white scales, simi- 

 lar to those of the under surface, and contrasting with the snowy whiteness of 

 the vittae ; the legs are speckled with dark fuscous, but the usual femoral band 

 is not seen. 



7. O. argentatus, niger, Eequaliter argenteo-albo-squamosus,vix variegatus, 

 rostro basi impresso, trisulcato, sulcis angustis profundis, lateralibus postice 

 paulo incurvis, thorace latitudine paulo breviore, inaequali canaliculato, pro- 

 funde grosse punctato, lateribus late rotundatis, elytris ovalibus, striis vix im- 

 pressis punctatis, interstitiis paulo convexis. Long. '69. 



One female, with the elytra nearly twice as wide as the thorax, found at Val- 

 lecitas, California ; the anterior and posterior marginal impressions of the tho- 

 rax are entire and very distinct, uniting with the dorsal line ; the color is more 

 uniform than in the other species, nevertheless the elytra are slightly mottled ; 

 an occipital line, the sides of the rostrum, and a space behind the eyes are covered 

 with fuscous metallic scales ; the dark band of the femora existing in many of 

 the species is more conspicuous in this, on account of the denser white scales of 



the legs. 



8. O. v a r i u s, niger, albo-squamosus, capite fusco- variegato, rostro bisul- 

 cato, basi impresso, versus apicem medio foveato, thorace latitudine non breviore, 

 subinajquali, subcanaliculo, grosse parce punctato, fusco trivittato, lateribus late 

 rotundatis, elytris striis tenuibus minus profunde at grosse punctatis, interstitiis 

 non convexis, 3io Stoque plus minusve fuscis. Long. "35 '44. 



Desert of the Colorado, California ; chiefly on Larrea Mexicana. The elytra 

 of the male are not wider, those of the female are twice as wide as the thorax. 



