90. Formica vigilans ^HNS. B.M.

Worker. Length 5, 1/2 lines.-Head, thorax, and scale of the abdomen, blood-red; the abdomen and legs black; the antennae, eyes and mandibles black; the face anteriorly, the clypeus and mandibles, smooth and shining, the latter with five stout teeth; the flagellum obscurely rufo-fuscous; the head posteriorly deeply emarginate and opake; the thorax opake, compressed; the coxae, extreme base of the femora and tibae, and the apical joints of the tarsi, ferruginous; the scale ferruginous, ovate and entire; the extreme base of the abdomen ferruginous. The entire insect thinly sprinkled with erect black pubescence.

Hab. Borneo (Sarawak).

In general form closely resembling F. compressa ^HNS; the thorax is shorter, the legs stouter, and F. compressa ^HNS is not pubescence