14 Randall's New Species of 
elytra pitchy black; stris rather shallow, punctured; 
apex obtuse: feet pale testaceous. 
Length between sixth twentieths and seven twentieths 
of an inch. 
18. ELATER TENUICOLLIs. 
E. graciliformi similis, sed corpore multo minore, = thorace 
penitus atro, minus convexo, margine vix curvato ; antennis nigris; 
elytris pallidis, testaceis; pedibus piceis. 
Nearly allied to E. gracilifórmis described above ; 
but the body is at least one half smaller, more slender: 
thorax less convex, entirely black ; margin nearly straight : 
the antenne are almost black: the elytra pale testace- 
ous, and the feet piceous. 
Length nearly five twentieths of an inch. 
Not so rare as the above. I have found it both in 
Maine and Massachusetts. 
19. Omatisus THORACICUS. 
O. corpore nigro; humeris rufo-sanguineis; thorace.anticé sub- 
quadrato. Angulis posticis prominentibus et sub-transversis, rhombo 
centrali elevato; elytris lineis — carinatis, cum carinulis inter- 
mediis; spatiis mediis valdé 
Body elongated, black, with bright rufous shoulders : 
joints of the antenne rather more cylindrical than com- 
pressed : labrum somewhat rufous at tip: thorax quad- 
rate anteriorly ; posterior angles prominent, somewhat 
transverse; middle with a much elevated rhomboidal 
ridge, winged laterally, and dividing the surface into five 
profound cavities; margin elevated: elytra each with 
five distinct, elevated lines, and three or four indistinct, 
