10. Polyrhachis irritabilis ^HNS.

P. niger, pube pallide aurea vestitus; thorace quadridentate, petioli squamula bidentata.

Female. Length 6 1 / 2 lines. Black, and densely clothed with short pale golden pubescence; all parts of the insect sprinkled with erect cinereous hairs; the mandibles shining black, the palpi pale testaceous; the head elongate, the eyes placed high on the sides of the head, ferruginous and very prominent. Thorax elongate-ovate; the prothorax with a short, stout, acute tooth on each side, slightly curved and directed forwards; the metathorax with a similar tooth on each side directed backwards; the wings subhyaline, the nervures fuscous; the legs fusco-ferruginous, the femora and coxae brightest. Abdomen ovate; the scale incrassate, armed above with two stout acute teeth.

Hab. Aru. This is probably the female of P. sexspinosus ^HNS.