LeConte.] 



CRYPTOEHTNCHINI. 239 



gradually into the club which is elongate, obtuse at tip, corneous at base, 

 pubescent on the outer half. Prothorax longer than wide, gradually nar- 

 rowed in front; broadly, but not deeply constricted in front, slightly pro- 

 duced at the middle, postocular lobes not well marked, base feebly sinuate. 

 Elytra a little wider than the prothorax, humeri rectangular, slightly 

 rounded, sides parallel, rounded at tip. Prosternum deeply and broadly 

 emargiuate in front, pectoral groove broad and deep, antecoxal ridges very 

 prominent, front coxae very prominent, narrowly separated, supporting the 

 end of the beak; prosternum behind the coxae not prominent; mesosternum 

 small, middle coxae narrowly separated; hind coxae distant, metasternum 

 with the anterior process nearly acute; hind margin broadly emarginate; 

 ventral sutures straight; third and fourth segments short, the others longer. 

 Legs short, stout, thighs not toothed; tibiae sinuate on the inner side> 

 strongly armed at tip; tarsi as long as the tibias, not dilated nor spongy be- 

 neath; last joint as long as the two preceding; claws slender, divergent, not 

 toothed. 



1. A. rigidus, n. sp. 



Elongate, black, covered thickly with dirty brown hair, and short, erect, 

 stout bristles, which conceal the sculpture. Prothorax longer than wide, 

 slightly rounded on the sides, broadly constricted near the apex, which is 

 rounded; base feebly bisinuate; dorsal channel faint. Elytra about one- 

 fourth wider than the prothorax, cylindrical, rounded behind ; striae composed 

 of quadrate punctures; first, third, fifth and seventh interspaces wider, more 

 prominent, and furnished with conspicuous rows of bristles; eighth and 

 ninth with a few bristles; second, fourth and sixth very narrow, not pro- 

 minent. Beneath, very coarsely punctured, covered with a dirt-colored 

 crust, with scattered, short, coarse hairs. Length 3-4 mm.; .12-.16 inch. 



South Carolina to Texas, not uncommon. Judging from a MS. drawing 

 by my ftxther, it is Botrobatys troglodytes \T)Q.i. Cat. 



Group III. €ryptorliyncIii. 



In this group the pectoral groove is distinctly limited behind. The other 

 characters are variable, though the front coxae are never contiguous as in 

 some Ithypori; a slight appearance of an epipleural fold exists in many 

 species. The claws are toothed in Phyrdenus, but simple, and generally 

 small in the other genera. 



The genera in our fauna are not numei'ovis, but present several categories 

 indicating sub-gi'oups, which it is unnecessary to define at present, as their 

 number would be increased by a careful study of exotic forms. 3ficromastus 

 might be placed with equal propriety in Ithypori, near Arthrostenus, but for 

 the present I prefer associating it with Acalles: the only specimen in my 

 collection is much broken. 



Metathoracic epimera distinct 6. 



" " indistinct 2. 



2. Metasternum as long as first ventral segment 5. 



Metasternum veiy short, humeri rounded 3. 



