174 JOHN L. LECONTE, M. D. 



HYLASTES Er. 



In this genus the nearest approach is made to the Cossonide type 

 of Khynchojjhora. The front part of the head is more distinctly pro- 

 longed into a short stout beak, which is obliquely excavated on the side, 

 for the reception of the scape of the antennae. The funiculus consists 

 of 7 distinct joints, of which the 1st is but little larger than the 2d ; 

 from the 2d to the 7th they are gradually a little wider; the club is 

 small, oval, not compressed, distinctly annulate ; the basal half is shining 

 and nearly glabrous; the prosternum is deeply excavated for the re- 

 ception of the head; the tibia; are broadly dilated and serrate; the 

 joints of the tarsi 1 — 3 are equal in length, the 3d emarginate, or 

 bilobed, the 4th equal to the two preceding united, not much thick- 

 ened at the tip. The 1st and 5th ventral segments are conspicuously 

 longer than the intermediate ones, and the sutures are straight, and 

 very deeply impressed. 



The chief character relied on by Dr. Zimmermann for the distinction 

 of his genus Ifijhu'ijH>^^ which corresponds with this, is generally true 

 but not very obvious ; but the scutellum is always on a level with the 

 base of the elytra, and the base of the thorax is not bisinuate. as in 

 Dcndrocfoiiiii^. 



ITijhistoi piiiniJiis Er., does not belong to the genus nor tribe, and is 

 referred to AijImiKirthrnm on page 152. 



The species before me may be grouped in the following manner, after 

 the two divisions established by Erichson. 



A. — Mesosternum truncate in front, third tarsal joint emarginute, 

 not dilated ; tibiae coai-sely toothed : 



a. — Beak more or less carinated : 



1. H. porculus Er. (Ante, p. 149 =ij. scabrvpennis.) 



2. H. cavernosus Zimm. (Ante, p. 149.) 



;;. H. nigrinus Mannh. Bull. Mosc. 18.">2, 356, (Ilj/largus); ibid. .38.j. 

 Alaska. Oregon and California. Very similar to //. corernosux^ but 

 the sides of the thorax are almost i)arallel for three-quarters of their 

 length, then rounded fco the ti}) ; the punctuation is more dense and 

 the elytra more rugose and more pure black. 



4. H. gracilis. — Elongate, blacki.<h-hri)wn, elytra and club<jf antenupe some- 

 what paler, thinly clothed with very short yellowish pubescence; head densely 

 ])ut not coarsely puncturec^; beak finely and distinctly carinate, broadly trans- 

 versely impressed near the tip; prothorax coarsely punctured, with a some- 

 what indistin<!t smooth dorsal line; it is longer than wid^e, and nearly straight 

 on the sides, the apex is broadly rounded, the base very feebly rounded; elytra 

 not wider than the thorax, with striae composed of lafge quadrate punctures, 

 intervals narrow, rugose and sparsely punctulate, convex towai'ds the tip and 

 suture; tibice coarsely serrate. Long, nearly 4 mm. 



