126 [Nov., 1846. 



inarkable for the emargination and number of the articulations of 

 the antenna?, which are more numerous than in any native species 

 hitherto described. The globular base of the second is not enu- 

 merated; twenty-four are imbricate, and the final one has a small 

 additional process rising out of its concavity. In P. imbricornh 

 the antennae of the male have nineteen, and of the female, seven- 

 teen articulations. 



3. Sphenostethus. Allied to Prionus. Head small, narrower 

 than the thorax, concave above; eyes slightly emarginate ante- 

 riorly ; antennae less than half the entire length, slender and com- 

 pressed, second articulation longest, subsequent, ones gradually 

 decreasing, with a tendency to serration beneath ; mandibles ro- 

 bust, toothed ; palpi with the terminal articulation triangular : 

 prothorax transverse, narrower than the elytra, contracted ante- 

 riorly, concave posteriorly, the external margins unarmed : pro 

 and mesosternum conjointly carinate, in close contact, the latter 

 entering an acute emargination of the former : scutel triangular : 

 elytra separately rounded at base, moderately tapering and 

 dehiscent; sides incurved, apex minutely serrate : feet slender. 



4. S; serripermis. Shining black, punctate scabrous above; front 

 with a wide depression having an impressed medial line; pro- 

 notum with two approximate impressed punctures upon each 

 side arranged diagonally, medial line visibly impressed poste- 

 riorly; external margins convex, emarginate at the posterior 

 angles ; posterior margin convex in the centre and concave late- 

 rally : elytra meeting the pronotum in close contact, a shallow 

 scabrous impression at the base ; apex finely serrate. Length 

 11 ; prothorax 2; elytra 8; width at base 4 lines. 



A single specimen taken in south-eastern Pennsylvania. An- 

 other seen in Le Conte's cabinet, probably taken in New York. 

 Probably allied to Prionus muticus, Fabr. ii. 265. It is remarka- 

 ble for the close contact of the prothorax with the elytra and scutel 

 above and the mesosternum below. 



5. Molorchus tenuipes. Black, frontal line deeply impressed : 

 prothorax cylindric : elytra dark fuscous, obsoletely fulvous at base : 

 medial and posterior feet very slender. 3 lines long. 



The larva inhabits detached branches of the genus Carya, 

 (hickory), the perfect insect appearing in May in S. E. Pennsyl- 

 vania. 



6. Enoplixjm venustum. Dark brown, with minute fulvous 

 hairs : middle of the elytra with a broad irregular transverse silvery 

 band. 4$ lines long. South-eastern Pennsylvania. 



Base and half the terminal articulation of the antennae, palpi, 

 anterior tarsi, and base of the femora, pale yellow : pronotum tu- 

 berculate : elytra with numerous dilated impressed punctures : 

 apex pale yellowish brown, and with the base marked with a 

 few small spots of yellow; the central white portion has several 



