peculiarity, for the smaller ones I have found burrowing during the summer months in vertical or sloping banks with a sunny aspect, whilst the males were hovering about both in the vicinity and close by, sometimes either playing or fighting on the wing with the very small _Nomadæ_, which infest these species parasitically, whilst their females were sedulously pursuing their vocation. Gradually these joyous spring insects lose their gayness and their brilliancy, as do those which have followed in succession of development with the growing year, and they become senile and faded and are lost as they have progressively fulfilled their function. By this time the ragwort is in bloom, and the thistle displays its pinky blossoms; now the males are to be found numerously exhibiting themselves upon these flowers, and also another equally fresh brood to those of the spring and early summer, of females. My friend the late Mr. Pickering, who was in the early days of the present Entomological Society, when it held its meetings in Old Bond Street, its honorary curator, and who was then and always, even when less leisure was afforded him from professional duties, a most assiduous and diligent observer of the habits of insects, propounded his theory, both in conversation and before the meetings of the Society, although he never drew up a paper upon the subject, that these females were then impregnated, upon which they retired to a hibernaculum, and there remained until the breath of a new spring brought them forth in all the beauty of their gay attire, and that it was from their broods deposited thus in the spring and early summer, that the autumnal insects were developed. This theory is both plausible and possible, and I have no doubt that it is the correct one; and thus is explained the total absence of males at the time of the appearance of the females in the foremost portions of the year; this habit we shall find also in the _Bombi_. The flowers they delight in, besides those previously named, are among others the ribwort plantain, and the bramble, as well as the _Umbelliferæ_ and the flowers of the broom. The females possess two remarkable distinctions of structure not found in any of the other bees, which consist in an articulated appendage in the centre of the front margin of the labrum, and a vertical cleft in the terminal segment of the abdomen, both of which will necessarily have their uses in the economy of the insect, although what these may be has not been discovered.