824 COLEOPTERA OP NORTH AMERICA. 



the contact of the sternal pieces. Episterna of metathorax long 

 and narrow, nearly pointed behind ; scent pores not very distinct, 

 though the insect has an offensive odor when alive. Hind coxae 

 rather convex, though distinctly separated. Ventral segments 

 nearly equal in length, 5th in semicircularly emarginate at tip. 

 Legs slender, hind pair longer, middle tibia? with a singular 

 oblique groove on the outer face, below the middle ; tibial spurs 

 distinct ; 1st joint of hind tarsi as long as the two following. 



Tribe XV. DESMOCERINI. 



This tribe is represented by two species of Desmocerus, D. 

 palliatus in the Atlantic, and D. auripennis in the Pacific States. 

 Though by the large conical and contiguous front coxae, and the 

 divided stridulating surface of the mesonotum it belongs to the 

 Lepturoid series, it differs remarkably from the other genera by 

 the much smaller and stouter mandibles, which are not at all 

 fringed on the inner margin. The ligula is large, membranous, 

 and bilobed, though less deeply so than in Lepturini ; the palpi 

 are short, not dilated ; the men turn is large, trapezoidal, and the 

 gular process very short. The eyes are finely granulated, nearly 

 rounded, suddenly and deeply emarginate towards the base of 

 the antennae, which are 11-jointed, with the joints 3-5 thickened 

 at the end, and the outer ones velvety black ; the vertex is 

 prominent, deeply sulcate, suddenly perpendicular in front of the 

 antennae, frqnt horizontal, advancing as in other Lepturoides 

 (and also in Distenia) between the base of the mandibles; labrum 

 large, not emarginate. Prothorax gradually wider behind, 

 obtusely angulated on the sides, hind angles prolonged, acute ; 

 scutellum rounded behind, stridnlating plate of mesonotum large, 

 divided by a smooth furrow. Elytra parallel, coarsely punctured, 

 obliquely rounded behind. Prosternum very narrow between the 

 coxae, which are large and conical with the cavities angulated 

 externally and open behind ; mesosternum narrow, subemarginate 

 at tip, coxal cavities widely open externally ; episterna of meta- 

 thorax wide, subparallel, suddenly narrowed behind. Hind coxae 

 prominent, contiguous at the inner side ; ventral segments sub- 

 equal ; legs slender, tibial spurs moderate, tarsi rather broad, 

 hind pair with 1st joint scarcely equal to the two following united. 



In the $ the 5th ventral segment is slightly emarginate at tip, 



