648 Coleopterological Notices, IV. 



OLIGOLOCHUS n. gen. 



The single species referred to this genus, greatly resembles Micro- 

 cholus striatus in its general features of form, sculpture and vesti- 

 ture, although much smaller in point of size, and would have been 

 referred to Microcholus were it not for the distinctly different struc- 

 ture of the mandibles, which are not large and prominent as in that 

 genus, but very small, thick, strongly arcuate, notched at apex and 

 broadly decussate when closed. 



The principal generic characters have been given in the table, and 

 those of minor importance are referred to in the description of the 

 single species given below. Oligolochus does not resemble Zygo- 

 baris either in habitus or structure. 



1 Oligolochus convexus Lee. — Proc. Am. Phil. Soc., XV, p. 422 

 (Zygobaris ?). 



Oval, moderately and evenly convex, polished, black, the legs 

 rufous ; vestiture very sparse and uneven, white, consisting of large 

 scattered scales towards the sides of the pronotum and on the median 

 line before the scutellum, also on the elytra toward the base of the 

 third and fifth intervals and a few widely scattered on the disk 

 toward the sides, the latter smaller and narrower ; on the under 

 surface sparse but more evident on the sternal parapleural ; all other 

 punctures of the upper surface bearing extremely minute setae. 

 Beak moderately slender, evenly, not very strongly arcuate, coarsely, 

 sparsely, unevenly punctate at the sides, as long as the prothorax, 

 feebly thickened toward base and slightly flattened toward apex, 

 the basal impression extremely feeble; antennae inserted a little 

 beyond the middle, the scape almost attaining the eye, the first 

 funicular joint longer than the next three, the second small, slightly 

 longer than the third ; club moderate, abrupt, oval, densely pubes- 

 cent, as long as the preceding four joints, with the basal joint one- 

 half of the whole. Prothorax one-third wider than long, the sides 

 very feebly convergent and distinctly arcuate from the base to the 

 well-marked subapical constriction, the apex not tubulate, three- 

 fifths as wide as the base, the median lobe of the latter small and 

 feeble ; impunctate line entire ; punctures coarse, not dense. Scutel- 

 lum very small, quadrate, impressed behind, glabrous. Elytra but 

 slightly longer than wide, a little wider than the prothorax and 

 three-fourths longer, hemi-elliptical, the apex narrowly subtruncate ; 



