AMERICAN PHILOSOPHICAL SOCIETY. 625 



SPIIERACRA Say. 

 Elytra entire ; tibiro emarginate; terminal joint of the tarsi 

 profoiUKlIy bilobated ; nails simple; head as long behind the eyes 

 as before them; thorax Buboylindric ; antenna) much shorter 

 than the body; basal joint mueh shorter than the head, 

 joints excepting the second not very une(jual in lengtli, subcy- 

 lindric ; labrum emarginate ; palpi with the terminal joint some- 

 what fusiform, subacute; mentum with a prominent acute cen- 

 tral tooth. 



S. DORSALIS Fabr. — " Black ; elytra striate, testaceous ; suture 

 broadly black. 



Inhabits Carolina. 



Museum of Mr. IJosc, 



Smaller than O. umjitstata. Antennae testaceous ; head black, 

 polished, broader than the thorax ; thorax cylindrical, obscurely 

 ferruginous; elytra striate, testaceous; suture broadly black, 

 hardly attaining the tip ; body black ; feet testaceous." Fabr. 



Odacantha i7ors(t/is Fabr. Syst. Eleuth. 1, 229. 



In my specimen the head only is black, or rather of so deep a 

 rufous as to appear black, excepting the tip and base. [413] 



This well known species was referred by its discoverer, Fabri- 

 cius, to his genus Oilarnnthn ; in which arrangement he was fol- 

 lowed by Dejean, who, however, was fully aware of its generic 

 difference from the 0. melanura, Fabr, Dejean, in his observa- 

 tions on the genus, says, " that in consequence of the joints of 

 the tarsi being less filiform than those of the type of the genus, 

 almost triangular, the penultimate one deeply bilobate and the 

 extremities of the elytra rounded, it would be perhaps proper to 

 make a new genus of this insect." In this remark I perfectly 

 coincide, as I cannot see the propriety of joining, in the same 

 genus, two insects whose characters in tjie artificial system place 

 them in different familie.H, though it cannot be denied that they 

 have many, more intimate, natural afiinities. 



I had written the above with the expectation of introducing 

 a new species, in an insect which, in form and color, resembles 

 the dorsalis exceedingly to the eye, excepting in size; but on 

 close examination it proves to be widely distinct. 



[This genus was previously described as Lcptotrachdm Fabr. 

 — Lec] 

 1834.] 



