Horn.] 



PROMECOPINI. 109 



slightly wider than the thorax (marmoratus) or not. Mesosternum protuber- 

 ant in the form of an obtuse spine. Metasternum moderate, side pieces wide. 

 Intercoxal process broad, oval at tip, second segment longer than the two fol- 

 lowing united, first suture strongly arcuate. Anterior and middle tibiae mu- 

 cronate, articular surface of hind tibioe internal, cavernous, the tip truncate, 

 and with oval scaly space. Claws free. Body oval, densely scaly. 



The scar left after the disappearance of the deciduous piece is small and 

 difficult at first to discover, and the genus was placed in the following sub- 

 family. (Amer. Nat. 1874, p. 461). Two other genera are very closely 

 allied to this, and should probably not be separated, Pororhynclius and 

 Periorges. The former has the thorax margined near the base as in 

 Coleocerus, but the mesosternum is not protuberant; the latter has the pro- 

 tuberant mesosternum, but not the thoracic margin. One of our species 

 (marmoratus) might be referred to Periorges, but the mesosternum is pro- 

 tuberant exactly as in Coleocerus, while in that genus the protuberance is 

 slight and somewhat laminiform. 



Two species occur in our fauna. 



Thorax margined at the sides, at base dispar. 



Thorax not margined marmoratus. 



O. dispar Lee. (Bathpris) Amer. Nat. 1874, p. 403. 



Form oblong oval, densely scaly. Head and rostrum as long as the 

 thorax. Rostrum deeply sulcate, moderately densely punctured, and 

 densely covered with rounded scales, of dark cinereous color, a paler 

 line on the vertex. Thorax rhomboidal. gradually narrower from base 

 to apex, sides dilated near the hind angles, and with a short sub-acute 

 ridge, disc moderately convex, densely covered with dark cinereous 

 scales, median line and sides paler, a small spot on each side of middle 

 darker. Scutellum Avhite. Elytra oblong, not wider than the expanded 

 thorax, striate, striae with moderately large punctures, intervals flat, 

 each M'ith a row of short, erect hairs; surface densely covered with 

 brownish scales; tip, and a short oblique band in front of middle cinere- 

 ous. Body beneath and legs densely covered with nearly white scales, 

 darker on the outer side of the legs. Length .18 inch; 4.5 mm. 



One specimen. Arizona, Dr. Webb. From memory alone, I am in- 

 clined to think this species identical with C. variegatus which I saw in the 

 cabinet of M. Aug. Salle, of Paris. 



O. marmoratus, n. sp. 



Form of disiMir, densely scaly. Thorax broader than long, sides mode- 

 rately arcuate, widest at middle, disc moderately convex, covered densely 

 with whitish scales, with black and fuscous sparsely intermixed, and a 

 transverse basal band black. Scutellum white. Elytra oblong oval, indis- 

 tinctly striate, and with moderately large punctures distantly placed, inter- 

 vals flat without erect hairs, surface densely scaly; scales cinereous and 

 brown intermixed, and with three very irregular black fasciae; the first ob- 

 lique, the second median, transverse, the third sub-apical. Body beneath 



