8 



the extremity of the apex they are subsinuated and 

 subacuminate, while in Tetracha they are rounded. 

 The head and antenna3 are in proportion shorter 

 than in Tet. Carolina and other allied species, 

 while the upper lip also projects, is more rounded 

 and armed with four small teeth. Mons. Lacordaire 

 states that the habits of this species differ fi*om the 

 MegacephalidsB, as it is usually found running 

 among the herbage in sandy situations and rarely 

 is seen to fly. The typical species is named Sepul- 

 chralis ; I apply to it the name of aviapos tristis, as 

 it is almost the only dark species of Megacephala 

 of my acquaintance. 



Sp. 10. Riparia, — Now of the Fabrician genus 

 Elaphrus. Mr. Stephens is apparently the first 

 Entomologist who considered these Insects entitled 

 to rank as a family. Mons. Laporte has I think 

 injudiciously united them to the Nebriadse, and in 

 this opinion M. M. Audouin and Brulle seem to 

 agree. Mr. Kirby is of a different opinion and 

 coincides with Mr. Stephens, and adds several 

 pertinent observations respecting the Elaphridse, 

 to which the reader is referred. Vide Fauna Boreali 

 Americana, p. 60. The following genera belong 

 to the family. 



