AMERICAN COLEOPTERA. 167 



intervals are marked with rows of equally distant punctures of little 

 smaller size. The front in the male is flattened, and fringed with very 

 long hair; the venter is coarsely punctured, concave towards the base, 

 with the anterior margin of the declivity prominent and subacute; the 

 hind margins of the third and fourth segments are smooth and ob- 

 tusely elevated ; the last segment has a longitudinal impression, and is 

 very hairy behind. 



6. S. sulcatus. — Blackish, elytra, antennse and feet yellowish brown, head 

 longitudinalJ.y aciculate, flattened, slightly hairy; prothorax not longer than 

 wide, strongly narrowed in front, very feebly rounded on the sides, finolj', not 

 densely punctured, more distinctly at the sides; elytra with the punctures of 

 the rows and intervals almost equal in size and distance, with a few short yel- 

 low hairs towards the side and tip, the tip, as usual, rugosely punctured ; ven- 

 ter not densely punctured, anterior part of declivity prominent, subacute, pos- 

 terior margin of the segments smooth and somewhat elevated. Long. 3"75 

 mm. 



One female. New York. The color of the elytra is probably va- 

 riable. Seems to resemble the European S. rugidosus. 



7. S. ventralis. — Black, shining, head longitudinally aciculate and punc- 

 tured, slightly convex and thinly clothed with short hair; prothorax oblong, a 

 little longer than wide, slightly narrowed in front, feebly rounded on the sides, 

 moderately punctured, more finely on the disc than at the sides; elytra with 

 approximate rows of punctures, those of the striae and intervals being equal in 

 size and distance, and bearing very short grayish hairs; tip rugosely punc- 

 tured ; venter somewhat concave, strongly, but not densely punctured, second 

 segment with a conspicuous tubercle at the middle of the hind margin; last 

 segment more acutely margined than usual, antennse ferruginous, feet dark- 

 brown. Long. 4 — 4*5 mm. 



Two specimens collected in Washington Territory, given to me by 

 Mr. George Gibbs. 



Tribe IV. — Hylurgini. 



The introduction of the genera Chramesus, Cnesmus and Polygra- 

 phus into our fauna requires a modification of the definition of this 

 tribe. 



The distinctions are to be found less in the degree of the dilatation of 

 the third tarsal joint than in the obsolescence of the fourth joint, 

 whereby the tarsi become in the tribe Ilj/hof/ mi tetramerous, as in the 

 normal Rhynchophora ; besides this difference in the tarsi, the head is 

 also larger and more prominent than in the Tomicini, and inserted in 

 the axis of the prothorax, instead of at an angle, as it is in the tribe 

 last named. The sculpture of the thorax is always uniform, a character 

 rarely observed in the Tomtcini, and the base of the elytra is fre- 

 quently elevated, acute and serrate ; finally the prolongation of the 



