6. Formica tropica ^HNS.

F. nigerrima, nitida, laevissima; thorace pubescente, postice compresso; pedibus rufo-nigris.

Worker. Length 3 1 / 4 lines. Jet black, smooth, shining, and having a faint prismatic lustre, particularly on the head / which is oblong, or subquadrate; the tips of the mandibles ferruginous. The prothorax rounded at the sides and in front; a deep constriction at the base of the metathorax, which is elevated and rounded above; the thorax has a loose long pale scanty pubescence, probably much more dense in specimens in fine condition; the legs very obscurely ferruginous, nearly black; the legs, particularly the tibiae, have a thin long loose pale pubescence. Abdomen thinly sprinkled with pale hairs; the scale of the peduncle rounded and blunt above, not much elevated. Hab. Gilolo.