1. Halictus ceratinus ^HNS.

H. niger; alis hyalinis; abdomine clavato. Male. Length 31/2 lines. Black: the head closely and finely punctured; antennae as long as the thorax, the flagellum obscurely testaceous beneath; the face covered with griseous pubescence; the mandibles ferruginous at their apex. Thorax closely punctured; the wings hyaline and iridescent, their apex slightly clouded; the nervures and tegulae testaceous; the legs rufo-testaceous, the tarsi paler, and covered with pale glittering pubescence. Abdomen clavate; the apical margins of the segments with fasciae of short white pubescence, frequently more or less obliterated; shining and delicately punctured; beneath, the apex of the third segment, and the fourth, entirely clothed with very short whitish pubescence; the abdomen is of a dark rufo-testaceous hue, palest beneath, varying in different individuals.

Hab. Borneo (Sarawak).

This remarkable form of Halictus ^HNS occurs at Sierra Leone. I have described a species from that locality, the " H. clavatus ^HNS;" it is a smaller and very distinct species from H. ceratinus; in this species the first recurrent nervure is received in the middle of the second submarginal cell.