16 . Cryptocerus obtusus ^HNS. B.M.

Worker. Length 2 1/2 lines. - Opake black: head large, wider than the thorax or abdomen; the sides margined before the eyes and obscurely ferruginous, widely emarginate in front; the posterior lateral angles of the head rounded, emarginate be- tween; the antennae rufo-piceous at their apex. Thorax: the prothorax transverse, with two blunt teeth on each side; the mesothorax narrowed to the base of the metathorax, the latter with a short tooth at its basal angles, the apical angles being produced into long stout obtuse spines. Abdomen ovate, nar- rowly margined, and deeply emarginate at the base, the margins at the base ferruginous; the nodes of the peduncle transverse, the second node with a short stout spine at the sides; the entire insect sprinkled with minute glittering scales.

Hab. Brazil (Santarem). (Coll. H. W. Bates.)