M. castaneo-rufus; thorace quadrispinoso; abdomine cordato.
Worker. Length 2 lines. Chestnut-red; the head and thorax palest; the head very delicately reticulated; the eyes small and black, placed at the sides of the head backwards near the vertex; the clypeus widely truncate in front. Thorax: punctured, the anterior margin somewhat transverse, slightly produced and rounded in the middle, the lateral angles acute; the sides rounded and narrowed to the base of the metathorax; the posterior margin transverse; at the angles are long acute spines, with a second shorter spine before them; the truncated vertical portion of the metathorax has on each side about the middle of the lateral margins a short acute spine. Abdomen: the first node, viewed laterally, is wedge-shaped, the second somewhat quadrate, its posterior margin above produced into an acute spine; the upper margin of the first node, truncate; the abdomen heart-shaped, acute at the apex; the entire insect sprinkled with erect pale hairs.
Hab. Borneo (Sarawak).
This is probably the worker of M. castaneus .
Worker. Length 2 lines. - Chestnut-red: the thorax with the anterior lateral angles acute, and armed posteriorly with four spines. The head and thorax paler than the abdomen, the head very delicately reticulated; the eyes small, black, and placed backwards on the sides of the head towards the vertex; the clypeus widely truncate in front. Thorax slightly rounded in the middle in front; the sides narrowed and rounded to the base of the metathorax; the posterior margin transverse, at each of its lateral angles a curved acute spine, with a shorter spine a little beyond them; the truncation of the metathorax with a short acute spine about the middle on each side. Abdomen: the first node, viewed laterally, is wedge-shaped, the second sub- quadrate, its posterior margin produced into an acute spine; the anterior margin of the first node truncate; the abdomen heart- shaped; the entire insect sprinkled with erect pale hairs.
Hab. Borneo (Sarawak). (Coll. W. W. Saunders, Esq.) This is probably the worker of M. castaneus .
