258 AnuaJs Entomological Society of America [Vol. X, 



The tribe Steatoderini is subdivided into the two subtribes, 

 Sericosomina to include the genus Sericosomus , and Steatoderina 

 to include Trichophorus, Orthostethiis, etc. The strongly convex 

 head of the larva of Sericosomus and the broad penta-tuberculate 

 mandibles with the single sense process (Boving 1910) on the 

 second antennal segment easily distinguish members of this 

 subtribe. The Steatoderina (Fig. 6) are the only Elateridae 

 bearing more than one sense process on the second antennal 

 segment. 



The tribe Agriotini is subdivided into the subtribes Agriotina 

 and Adrastina. Agriotina (Fig. 7) is characterized by 

 two deeply pigmented invaginations of the epidermis on the 

 base of the ninth abdominal segment. These are not connected 

 with the tracheal system and their function is problematical; 

 they occur nowhere else in the Elateridae as far as we know. 

 The Adrastina agree with the Agriotina in the adult condition, 

 but the larvae are easily separated by the absence of the above 

 mentioned invaginations and by the presence of transverse 

 rows of setiferous tubercules on the ninth abdominal segment. 

 Betarmon is hardly distinguishable in the larval stage from those 

 species referred to our subtribe Adrastina. The adults have 

 been referred to the tribe Pomachilini, which tribe is diagnosed 

 by Candeze largely on habitus. They approach in one direction 

 the Agriotina, in another the Elaterina and in another the 

 Physorrhina. The tribe is probably a miscellaneous collection 

 of genera which will eventually be referred to other tribes. 

 Ectinus, the larva of which has been described by Henriksen, 

 does not fall in either of these categories, but undoubtedly 

 belongs in this tribe. 



The tribe Elaterini is subdivided into the Elaterina and 

 the Dicrepidina. In the former the transverse muscular 

 impressions on the tergites of the abdomen are parallel with the 

 anterior and posterior margins of these tergites, while in the 

 Dicrepidina (Fig. 8) they are obliquely placed upon the 

 tergites. The adults in the subtribe Elaterina never bear 

 lobes on the tarsi, while in the Dicrepidina the second and third 

 ioints at least are lobed. 



