366 Trans. Acad. Set. of St. Louis. 



convex, not impressed, the basal angles rounded; median frontal 

 grooves represented by feeble punctiform impressions at some distance 

 behind the epistoraa, the lateral oblique or ocular grooves short but 

 more distinct; prosternum very short before the coxae; thoracic side 

 margin gradually and evenly deflexed anteriorly from behind the middle, 

 remaining rather distant from the lower margin even at apex; hind 

 tarsi short and rather slender, with the first four joints regularly de- 

 creasing in length. Neotropical regions '''Dinolinns 



Antennae normal, as long as the head or longer, the basal joint much less 

 than half as long as the remainder; middle coxae larger and less re- 

 motely separated ; body much smaller in size and of more slender form, 

 the side margin of the prothorax strongly deflexed anteriorly from 

 behind the middle, becoming very narrowly separated from the lower 

 margin toward apex; fourth joint of the maxillary palpi spindle-form, 

 distinctly longer than the third, obtusely narrowed only toward tip; 

 mandibles unimpressed externally 7 



7 — Epistoma rather large, parallel-^ided, with its apex truncate and its 

 upper surface impressed; middle pair of frontal grooves short, double; 

 punctures of the head moderately coarse, normal, not forming grooves, 

 the sides evenly convex from the upper to the lower surface, the basal 

 angles evenly rounded; elytra not punctured in definite series. Mexico. 



*Saurohypnn« 



Epistoma small, gradually enlarged from base to the truncate apex, the two 

 duplex grooves of the front long and conspicuous, the oblique ocular 

 grooves short but deep; punctures of the head extremely coarse and 

 deep, subcoalescing into longitudinal grooves toward and on the 

 flanks, the latter otherwise evenly convex from the upper to the under 

 surface, the basal angles, however, not evenly rounded but obtusely 

 Bubpromlnent; elytra each with a distinct medial series of punctures. 

 Europe, — also occurring in America by accidental introduction. 



EnlissQS 



8 — Body much more depressed, polished, subimpunctate, the head trun- 



cate at base with the angles not rounded, though scarcely at all promi- 

 nent, the mandibles not grooved externally, the epistoma very short, 

 broadly truncate at tip, the median pair of frontal grooves long, deep, 

 strongly converging posteriorly, the median line thence deeply grooved 

 almost to the base, the short subsidiary grooves outside of the median 

 pair at apex fine and diverging as in the two preceding genera; ocular 

 grooves very coarse, deep, longitudinal, extending almost half way to 

 the base. Impressed; sides of the head obliquely flattened and with fine 

 punctuation, the under surface fiat, with coarBe impressed lateral 

 grooves which are bounded externally by a tumid line; last joint of the 

 maxillary palpi scarcely as long as the third, spindle -form, rather nar- 

 rower than usual, parallel, becoming obtusely acuminate only toward 

 tip; elytra not distinctly punctured; side margins of the prothorax 

 rather abruptly deflexed anteriorly from somewhat before the middle, 

 coming very close to the lower margin at apex. Central America. 



'^Homalolinnt 



9 — Body rather stout, parallel and convex, much smaller in size, the head 



broadly, feebly arcuate at base with the angles narrowly rounded, im- 



