50 U. S. p. R. R. EXP. AND SURVEYS — ZOOLOGY — 47TH PARALLEL. 



E. sulcipennis. I formerly considered this as a geographical variety of E. obscura, hut it 

 differs in having a larger and less convex thorax. I am not yet sufficiently advanced in the 

 study of this very difficult genus to determine whether it should be placed as a species or as 

 a race. 



E. granidata, elongato-ovata, nigra parum nitida, capite thoraceque suhaequa liter punctatis, 

 hoc subquadrato, minus convexo, latitudine paulo breviore, lateribus rotundatis, ad basin vix 

 sinuatim rotundato, angulis posticis obtusis rotundatis, elytris thorace latioribus, ovalibus apice 

 valde declivibus subacutis, dorso minus convexis seriatim granuUtis et parce muricato-pnnctatis, 

 versus suturam subseriatim punctatis ; humeris subproductis ; prosterno postice producto ; femo- 

 ribus muticis. Long. '58. 



Oregon ; Col. McCall. This and the next species are somewhat similar in form to E. quadri- 

 collis, but are less convex. The sculpture of the elytra is peculiar, being formed of small, some- 

 what shining, flat tubercles, arranged in series, with intervening scattered acute elevated 

 punctures. 



E. humeralis, longior ovata, atra opaca, capite thoraceque densius punctatis, hoc parum 

 convexo, latitudine paulo breviore, subquadrato, postice angustiore, lateribus rotundatis, ad 

 basin fere truncato, angulis posticis obtusis, elytris ovalibus, thorace latioribus, obsolete striatis 

 dorso depressis ad apicem subacutis valde declivibus, granulis subacutis parvis minus confertim 

 inordinatim positis, versus suturam punctatis ; prosterno postice perpendiculari, femoribus 

 muticis ; tibiis anticis calcari interno duplo longiore. Long. '57 — "65. 



Wenass river to Fort Colville ; Dr. Cooper. Readily distinguished by the foregoing char- 

 acters. By the larger size of the spur of the anterior tibias, it tends towards E. tricostata, and 

 several nondescript species. 



E. cordata. Specimens of three forms, allied to this species, were obtained in Oregon, and, 

 although evidently differing from those collected by me in California, I am not able to decide 

 regarding the propriety of separating them. They may be known by the thorax being more 

 broadly dilated^ and more regularly rounded on the sides, although equally densely and 

 coarsely punctured ; the posterior sinuation is therefore much shorter, although the basal angles 

 remain rectangular. The other distinctions are as follows : 



1. E. rotundipennis. Thorax very much constricted behind, fully one-half wider than lo ; 

 elytra as coarsely, but less densely punctured. Length, "45 — '55. 



2. E. striata. Thorax less suddenly, but very much constricted at base, fully one- alf 

 wider than long ; elytra more coarsely and less densely punctured. Long. '62. 



3. E suUigata. Thorax only moderately constricted at base, scarcely wider than long ; 

 elytra punctured as in E. cordata. Length, "44. 



Helops Fabr. 



H. Icelus, supra piceo-aeneus pernitidus, capite thoraceque confertim punctatis, hoc lateribus 

 fortius marginatis, margine rufo-piceo, angulis anticis valde rotundatis, posticis subrectis sub- 

 rotundatis ; elytris striis profundis, interstitiis parce punctulatis, ante medium lateribus paulo 

 concavis ; subtus rofo-piceus. Long. "33. 



One specimen, Steilacoom, Mr. Gibbs. Somewhat allied to IT venusfus Say, but smaller and 

 broader, with the sides of the thorax broadly margined, and the spaces between the strife of the 

 elytra less convex. 



