6. Ponera mutabilis ^HNS.

P. ferruginea, laevis, nitida, chalybea, viri-descens; abdomine rufo-fusco.

Worker. Length 3 1 / 4 lines. Ferruginous; the head and thorax with tints of blue in certain lights; the mandibles longitudinally and finely striated, armed with three teeth at their apex, and a fourth on their inner margin a little way within; the eyes ovate and placed forwards at the sides of the head. Thorax compressed posteriorly; the scale of the peduncle flattened, rather thick, with its superior margin rounded. Abdomen slightly fuscous; the apical margin of the basal segment slightly constricted.

Hab. Celebes (Tondano).

This species resembles the P. viridescens from Sarawak, but is at once distinguished from it by its much shorter and thicker antennae.