CERAMBYCIDAE. 309 



nearly equal in length, 5th in % seniicircularly emarginale at tip. 

 Legs slender, hind pair longer, middle tibiae with a singular 

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

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



Tribe XV.— DESIWOCERIIVI. 



This tribe is represented by three speeies of Desmocerus, D. 

 ■jjalUatus in the Atlantic, and two others in the raciJic States. 

 Though by the large conical and contiguous from coxa?, and the 

 divided stridulating surface of the niesonotuui it belongs to tiie 

 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 nientum 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, front horizontal, advancing hs in other Lepturoides 

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

 large, not emarginate. Pi'othorax gradually wider behind, 

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

 scutellura rounded behind, stridulating 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; mesosteruum 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 sul)- 

 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, 

 and the antennae are stouter. The insects are found on species 

 of Saiubueus. 



