AMERICAN COLEOPTERA. 107 



First joint of anterior tarsus, % spongy only at a]iex; seventh olytral striae 

 either entirely obliterated or replaced by fine distant punctures. 



(STENOUS,Chaud.) 

 Thorax gradually broader from base to apex, sides not sinuate behind. 

 Elytral stria3 faint and with punctures in theirentire length : tibite pale 



testaceous cupraeus. 



Elytral strine deeper, inipunctured ; legs entirely piceous Lecontei. 



Thorax with sides distinctly sinuate behind; elytral striae distinct, jmnc- 



tured only at base elegans. 



Ligula and paraglossre more or less connate; first joint of atiti'iior tarsus 

 % , spongy only at apex, seventh elytral stria either obliterated or re- 

 placed by distant fine punctures (CROSSOCREPIS, Chaud.) 



Striae inipunctured, seventh wanting quatuordeeimstriatua. 



Striae punctured, seventh replaced by a row of indistinct puuctures-.tszanus. 



0. amaroides, Dej. Sp. v, C64. 



This species is the smallest of the group to which it beloniis, and 

 recalls in its general aspect the species of Ajnai-a allied to impuncti- 

 coUis. The sides of the thorax are rounded and gradually broader to 

 the basal angle and not as in the two succeeding species narrower at 

 base than at a short distance in front. The median and basal impres- 

 sions are so fliint that they may be called obsolete. The elytra have 

 feebly rounded sides, are sub-parallel and very obtuse at apex. The 

 striae are moderately distinct, finely punctured their entire length, but 

 less distinctly at apex, the seventh being fully as distinct as the two 

 preceding stride. The intervals are flat, that between the second and 

 third striae with two distinct punctures. The meso- and metasternal 

 side, pieces are coarsely punctured, the sides of the abdomen rugous. 

 The legs are piceous-black. Length .30 — .36 inch ; 7.5 — 9 mm. 



Occurs from Pennsylvania to Texas, and westward to Kansas. Not 

 abundant. 



0. americanus, Dej. Spec. II, 377. — Black shining. Thorax gradually broader 

 from apex to base, slightly narrower at base than immediately in front, sides 

 rounded, disc feebly convex, and with the median impression distinct but not 

 deep. Elytra sub-parallel, very obtuse atape.^,seven-striate, striae moderately 

 deep, distinctly and closely punctured, intervals feebly convex and with two 

 punctures as in the preceding species. Meso-and metasternal side pieces 

 coarsely punctured: sides of abdomen punctured and finely wrinkled toward 

 the hind margins of the segments. Length .50 inch; 12.5 mm. 

 Occurs from Pennsylvania to Georgia, but not common. 



0. fluvialis, Lee. New Species, p. 13. 



■ Allied to the preceding species, but narrower and more convex. 

 The sides of thorax'are less rounded in at base, the median line more 

 distinct and the elytra proportionally longer. The stria3 of the elytra 

 are less deep, are very finely and distantly punctured. Intervals flat, 



