152 ACADKMY OF NATURAL SCIENCES 



Length ninc-tweutieths of an inch. 



This very distinct species is much less robust than the pre- 

 ceding ones, and is considerably contracted at the junction of the 

 thorax and abdomen. Under bison dung with the foregoing 

 species. 



The terminal joint of the maxillary palfji of these three species, 

 corresponding in its dilatation and form with the definition of 

 the Fabrician genus Blaps by Mr. Latreille, in the Regne Ani- 

 mal, I have referred them to the genus Asida, as that to which 

 they arc most closely related, though the form of the body 

 perhaps better agrees with Akin. 



[This is the type, and thus far, the only species of Pactostoma 

 Lee. Journ. Acad. Nat. Sci. 2d ser. 4, 19. — Lec] 



BLAPS Fab.Latr. 

 1. B. suTURALis. [Ante 1, 30.] [258] 



B ACUTA. [Ante 1, 31.] [259] 



3. B. OBSCURA. [Ante 1, 32.] 



4. B. HispiLABRis. [Ante 1, 32.] [260] 

 Length from three-fifths to nearly one inch. 



It is very possible that under this specific denomination, I 

 have confounded two distinct species ; but it seems probable that 

 the three preceding si)ecies are subject to vary a little in the 

 form of the thorax, and in size. I forbear separating them for 

 the present. 



[This and the three preceding belong to the genus Eleodes. 

 Idonotconsider this as sufficiently distinct from E.ohsaura. — Lec] 



5. B. CARBONARIA. — Black ; elytra with five or six regular 

 series of punctures ; impressed striae none. 



Inhabits the margins of the Arkansa river. 



Body oblong, deep black, immaculate, punctured: head acutely 

 punctured : labrum with black, rigid hairs : thorax subquadrate, 

 punctures smaller than tho.se of the head, and much more dis- 

 tant ; lateral edge regularly arquated : anterior edge very 

 slightly concave; posterior edge nearly rectilinear, a little ar- 

 (juated each side near the angles, which are obtuse : scutel 

 slightly indented near the tip, impuncturcd : elytra with about 

 six regular series of punctures, which arc more distant from 



[Vol. III. 



