The third species (Elaphomia alcicornis, the elk-horned deer-fly) is a little smaller than the two already described, but resembling in colour Elaphomia wallacei.

The horns are very remarkable, being suddenly dilated into a flat plate, strongly toothed round the outer margin, and strikingly resembling the horns of the elk, after which it has been named.

They are of a yellowish colour, margined with brown, and tipped with black on the three upper teeth.

The fourth species (Elaphomia brevicornis, the short-horned deer-fly) differs considerably from the rest.

It is stouter in form, of a nearly black colour, with a yellow ring at the base of the abdomen; the wings have dusky stripes, and the head is compressed and dilated laterally, with very small flat horns; which are black with a pale centre, and look exactly like the rudiment of the horns of the two preceding species.