CALOSO'MA, a genus of Coleoptorous Insects belonging to the acction Gcodephaga (M`l.stay), and family Carabiela.. It is known by the following characters :—Three basal joints of tho anterior tarst, in the males, much dilated, the fourth joint slightly so; antennas with the third joint longer than the rest; labrum bilobed; mandibles simple, slightly bent, and transversely striated; thorax short ; elytra generally rather broad and short.
This gonna is very closely allied to the true Carabi; indeed so much so, that it is to point out any very tangible distinguishing and yet the entomologist is seldom puzzled in separating them, even without close examination.
There is a considerable difference in the general appearance of the species of the two genera, end we think this in a great measure arises from the comparative proportions of the head and thorax. In Calosoma these parts are always smaller and considerably shorter in proportion to the body (which is generally broad) than in Ca rebus. The eyes are generally more projecting ; and M. Dejetui mentions the larger-sized jaws, and their being always transversely striated, AS a good distinction.
To the genus Calosoma belongs our largest end most beautiful British Cambidcons insect, the C Sycophanta. It is about an inch long ; the head, thorax, and under parts of the body arc of n beautiful blue colour, and the elytra are green, with red reflections more or less con spicuous in different examples; the legs and antennas are black.
Most of the best British collect ions contain this insect, and some even several specimens : it must nevertheless be considered is rare insect in this island, hardly ever more than one specimen having been found at one time. In France and Germany it is not uncommon, and is found in woody districts. Most of the British specimens have been token on the am coast.
C. Inquisitor is the only other species of this genus found in this country. It is about three-quarters of an inch in length, and of a bronze or brassy-green above, and black beneath. This species, though by no means common, is far more abundant than the last. It has been frequently met with crawling up the trunks of oak-trees in the spring of the year, about the time that that tree begins to put forth its leaves. Most probably it feeds upon the young caterpillars, which are then abundant.
Unlike most genera of insects, this appears to be confined to no particular quarter of the globe, species having been met with in almost all countries. About thirty species are known ; their prevailing colours are various shades of green, generally of a brassy hue, and sometimes black.