3. Odontomachus malignus ^HNS.

O. ferrugineus; capite supra oblique striato; margine interno mandibulorum confertim serrato; metathorace transversus striato; squama unispinosa; abdomine laevissimo.

Worker. Length 7 lines. Ferruginous; the flagellum and legs palest; head much narrowed behind, the posterior margin deeply emarginate; mandibles smooth and shining, their inner margin strongly serrated, their apex abruptly bent or elbowed, and armed with two stout teeth; the face anteriorly evenly striated obliquely; the head behind the anterior sulcation very delicately striated obliquely. The prothorax smooth and shining, the meso- and metathorax transversely striated. Abdomen very smooth and shining; the node of the petiole incrassate and tapering upwards into an acute spine.

Hab. Aru.

This species most closely resembles O. maxillaris ^HNS from Brazil; but its smooth polished prothorax alone would distinguish it; its head is much broader anteriorly, and less elongate.