The MALE differs in having the head less conspicuously globose; the cheeks less protuberant; the whole body more pilose, the anterior spurs robust, short, and abruptly obliquely truncated; the antennæ slender, filiform, much longer than in the female, but not much longer than the head, and from the fourth to the ninth joints serratulate within, adapting it to a sharp curve; the abdomen being equal, cylindrical, retuse at its base, convex above, and flat on the venter, where it has a longitudinal deeply concave mucro in the centre of the second segment, which concavity runs along all the subsequent segments, and it is densely pilose on the fourth; the terminal dorsal segment being deeply emarginate in the centre and produced on each side into a broad obtuse process; the claws are more robust than in the female and bidentate; the posterior pair being subclavate, and their single tooth abruptly reflected.
NATIVE SPECIES.
1. florisomne, Linnæus, ♂♀. 3-5 lines. ([Plate XIII.] fig. 2 ♂♀.)
maxillosa, Linnæus.
maxillosa, Kirby.
2. campanularum, Kirby, ♂♀. 2-2½ lines.
GENERAL OBSERVATIONS.
These insects are named from χηλὴ, a forceps, and στόμα, a mouth,—in allusion to the forcipate form of the mandibles, which are strong, and cross each other in inaction.
They and the next genus are styled carpenter bees, but they are not more consistently thus called than might be Anthophora furcata and the genus Ceratina; they, in fact, like the latter, just as often avail themselves of an empty straw to form their cells in, or the cylinder that has been drilled by some xylophagous beetle of their own size, as they themselves drill into palings and solid wood for the purpose, but when they do this, it is facilitated to them by their powerful mandibles and their square and strong head. They are certainly very compactly formed, their structure being indicative of great power, of course relatively to their size. When they drill their cylinders themselves they are extremely persevering in its execution, and in the process, the material they extract, which is like fine sawdust, they withdraw from the depth of the cavity by passing it beneath them, and pushing it out at the orifice by means of their posterior legs and the apex of the abdomen, for they are too long to be able to turn within the cavity they have formed, its capacity not being sufficient to permit this, as it is very little larger in diameter than themselves. I have repeatedly watched them in these operations.
Having found or drilled a suitable cylindrical tube, they do nothing further to it but collect a sufficient store of provender for the nutriment of the young one, upon which they deposit the egg which is to produce it. The insect then flies away to collect a small quantity of clay intermingled with sand, and this they knead together by means of a viscous secretion which they disgorge, and this forms a concrete that hardens firmly and rapidly; to anticipate its rapid drying they speedily fly back, carrying this small ball within their mandibles, and with it they cover over the provision they have collected, and which, adhering to the sides of the cavity, forms a firm and hard division, effectually separating it from the next store of provision that is to be accumulated for the supply of the larva that will be hatched from the egg that is to be deposited, and the same process is repeated again and again until all the eggs are laid. In their development, which takes place near midsummer, the males precede the females by about ten days. They associate sometimes in colonies, often using the tubes of the straw thatch which covers cottages for their nidus.