be reasonably entertained. This dissimilarity of the sexes is important to be noticed, on account of the difficulty of determining such exotic species of Xylocopæ as are closely related to each other. The propriety of giving Xylocopa Moris Fab. as a synonym of the female of the insect in question, or Apis Brasilianorum as that of the male, as Mr. Guilding has done, is extremely questionable. Mr. Westwood, whose opinion is of so much value on a point of this kind, has scarcely a doubt that the Xylocopa Chrysoptera of Latreille (Humboldt's South Amer. Zool. Pl. XXXVIII. fig. 1,) is the female of X. Brasilianorum.
XYLOCOPA CORNIGER.
Plate XXI. Fig. 3.
This figure represents a very large, nondescript, and unique species of Xylocopa, from the collection of the Rev. F. W. Hope. Mr. Westwood, to whom we are indebted for a beautiful drawing of it, proposes to name it X. Corniger, on account of two short strong horns upon the back part of the head, a character which does not occur in any other known species of the genus.
It is entirely black and shining, the upper surface of the thorax and abdomen being entirely destitute of hairs. The front of the head is broad, and bears two oblique elevated shining ridges above the mouth, and between the posterior part of the eyes are two short thick horns. The abdomen is long and depressed, with fascicles of black hairs on the sides and extremity. The wings are black and very glossy, with a
