South American species of Diahrotica. 15 



Head triangular, not longer than broad; clypeal ridge rather 

 strongly raised, but abbreviated before reaching the anterior margin 

 of the clypeus ; antennae robust, nearly equal to the body in 

 length, the second joint short, the third nearly twice the length of 

 the second, the fourth longer than the preceding two united, the 

 seven upper joints in the <? distinctly thickened. Thorax nearly 

 twice as broad as long ; sides nearly straight and slightly diverging 

 from the base to the apex ; upper surface broadly excavated trans- 

 versely, the excavated portion faintly impressed on either side with 

 a large shallow fovea. Elytra rather closely punctured, not plicate 

 below the humeral callus. 



The excavated thorax at once distinguishes the present 

 species from either of the preceding ones. 



Spec. 17. Diahrotica pectinicornis. 

 Ent. Month. Mag., xxv., p. 252. 



Elongata, postice paullo ampliata, modice convexa, pallide 

 flava, nitida, tibiis, tarsis capiteque nigris, antennarum articulo 

 penultimo albido, thorace transversim excavate ; elytris subcrebre 

 punctatis, nigris, limbo laterali, fascia prope medium apiceque 

 flavis. 



Mas, Antennis pectinatis, articulis penultimis duobus incras- 

 satis, difformibus. 



Long. 3 lin. 



Hah. Colombia; Cauca. A single specimen in my 

 own collection. 



Head triangular, not longer than broad, coarsely punctured on 

 the vertex and lower face ; clypeus with a distinct longitudinal 

 ridge ; antennae longer than the body in the 3' > the second joint 

 very short, obcouic, the third one scarcely half the length of the 

 second, turbinate, the fourth nearly as long as the three basal ones 

 united, the fourth to the eighth each with its upper and inner angle 

 produced upwards and inwards into an acute tooth or process, these 

 teeth increasing in length on each succeeding joint ; the ninth and 

 tenth joints strongly thickened, sinuate on their inner margins, 

 the ninth armed at its inner apex with an acute tooth, the tenth 

 bidentate at its inner base, the eleventh joint slender, cylindrical. 

 Thorax nearly twice as broad as long ; sides nearly parallel and 

 slightly sinuate from the base to beyond the middle, thence con- 

 verging towards the apex, the anterior angle distinctly produced, 

 broadly obtuse, the hinder subacute ; upper surface transversely 

 excavated on the middle disk, finely but sparingly punctured. 



