452 REVISION OF THE ELATERID.E 



relations are not known in all the species. I have endeavoured to point out such dis- 

 tinctive characters as appear to be independent of sex, but am very doubtful about the 

 correctness of the results; although the differences of the posterior thoracic angles, the 

 striae of the elytra, and the constriction of the last joint of the antenna? are very consider- 

 able, yet until the sexual relations are fully understood, no great confidence can be felt in 

 such characters, where the external appearance is so uniform. 



This supposed species has the posterior angles of the thorax very small, not at all di- 

 vergent, and acute; the sides of the thorax are broadly rounded, more so in (the female?) 

 one sex than in the other; the last joint of the antennae is strongly constricted and acu- 

 minate. The colour varies from dark reddish brown to castaneous; the pectus is some- 

 times darker than the abdomen; the feet are paler. 



9. A. tener, vakle elongatus, rufo-castaneus, helvo-pubescens, thorace elongato, antrovsum sub- 

 angustato, lateribus rectis, confertim punctato, minus convexo, angulis posticis acutis, paulo proiluctis, 

 non divcrgentibus, elytris striis anticc subtiliter punctatis, interstitiis fere planis, punctatis, antennis 

 articulo ultimo non constricto. Long. 'GO. 



One specimen, New York; possibly the true male of the preceding; the angles of the 

 thorax, though longer are still acute; the sides are straight, except at the very apex, 

 where they are slightly rounded; the dorsal line is visible only at the base; the antenna} 

 are scarcely longer than in the preceding, but their last joint is not constricted. It has 

 the general appearance of Corymbites pyrrhos, but the thorax is less elongate, and the 

 posterior angles less produced. 



10. A. consentaneus, fusco-piceus, helvo-pubescens, thorace latitudine longiore, ante basin 

 non latiore, lateribus ante medium late rotundatis, angulis posticis paulo productis, apice rotundatis, 

 confertim punctato, postice subcanaliculato, elytris striis antice profundius punctatis, interstitiis paulo 

 convexis, punctatis, pedibus antennisque ferrugineis, vel piceis, his articulo ultimo constricto. Long. -65- 



One specimen from New York, having reddish feet and antenna?, and another from 

 Michigan with the same parts dark brown. This species seems different on account of 

 the longer and more obtuse thoracic angles, which prevent it from being associated with 

 cither of the two preceding; the thoracic angles do not diverge at all, in which respect with 

 differs from the next, but may, nevertheless, be the male of it. The thorax is as densely 

 punctured as in A. melanopthalmus. 



11. A. bilobatus, nigro-piceus, helvo-pubescens, thorace latitudine longiore, convexiusculo, 

 medio parcius, lateribus sat dense punctato, lateribus vix late rotundatis, angulis posticis paulo pro- 

 ductis, divcrgentibus apice rotundatis, elytris striis antice profunde punctatis, interstitiis paulo con- 

 vexis punctatis, pedibus ferrugineis, antennis fuscis, articulo ultimo constricto. Long. "60. 



Mater bilobatus Say, Trans. Am. Phil. Soc. 6, 174. 



One specimen, Wisconsin, Dr. Hoy. Say describes the antenna; as of the same colour 

 as the legs, but we see from the preceding species that this is not a constant character. 

 This one differs by its more convex and less densely punctured thorax, and the more di- 

 vergent and more rounded angles; the sides of the thorax are very slightly rounded, and 

 are a little sinuous near the posterior angles. From all the others, except the preceding, 

 this is known by the more deeply punctured stria? of the elytra. 



