lead us to apprehend that several of the kinds of Xylocopæ, now regarded as distinct species, may ultimately prove identical, when we obtain as correct information regarding them as we possess in the present instance. The male (fig. 1,) is entirely tawny-yellow on the upper side, and blackish beneath; wings rather pale yellow, antennæ yellow on the under side, legs likewise tawny, the hairs of the two anterior pair paler yellow. The female (fig. 2,) is deep black, the wings broad and of a brassy hue, with purple reflections. The difference between the sexes is not confined to colour, but extends likewise to form. The male is comparatively slender, the thorax oblong, and the head small; the female has a very large head, and an orbicular thorax, the whole body appearing short and massive. These differences appear more conspicuous in Mr. Westwood's drawings, from which the accompanying engraving is taken, than in Mr. Guilding's figures; but Mr. Westwood's are carefully drawn from Guilding's own series of specimens, which are now in the possession of the Rev. F. W. Hope, so that no doubt can possibly attach to the identity of the insects. It may be said that the evidence from which they are inferred to be the sexes of one species is not absolutely conclusive, for no one has ever witnessed their union; but Mr. Guilding constantly found both of them in company, frequenting the same holes, the dark individuals being invariably females, and the other males, which affords so strong a presumption in favour of the opinion he formed, that little doubt on the subject can
