10. Formica diligens. F. obscure rufo-picea; antennis, mandibulis, thorace subtus et lateribus, metathorace pedibusque laete rufis; abdomine subtus pallide rufo-testaceo. Female. Length 9 lines. Head shining, dark rufo-piceous; the carinae at the insertion of the antennae, the antennae, the anterior margin of the face and clypeus, and the mandibles, ferruginous. The thorax and legs ferruginous, with the mesothorax above and the scutellum dark rufo-piceous; wings subhyaline, the nervures and tegulae pale ferruginous. Abdomen shining dark rufo-piceous, beneath pale rufotestaceous; scale subquadrate, its superior margin slightly emarginate its entire width. Hab. Malacca. This insect closely resembles the F. ligniperda.

Published as part of Smith, F., 1857, Catalogue of the hymenopterous insects collected at Sarawak, Borneo; Mount Ophir, Malacca; and at Singapore, by A. R. Wallace., pp. 42-88 in Journal of the Proceedings of the Linnean Society of London, Zoology 2 on page 55