A HISTORY OF NORFOLK part of the body is moved a little up and down produces the squeak. This kind of file and scraper arrangement is not uncommon amongst beetles, but there is considerable diversity in the situation of the apparatus and the organs involved. The common oil-beetle {Meloe proscarabceus), a large heavy blue black insect with oval pointed wing-cases which over- lap at the base, is so-called from the power which it possesses of exuding a clear yellow fluid from its joints when handled. On this account, although it is common enough in grassy places in the spring and early summer, it is by no means a prepossessing object. Its claim on our attention is due to its wonderful metamorphoses, the latter having been for the most part well ascertained. The female deposits an immense number of minute yellow eggs, in from two to four batches. These eggs are glued together and deposited in small holes in the ground, dug by the parent beetle. After an interval of from three to six weeks the young larvas hatch out ; they are extremely small elongate orange yellow insects with the body nearly parallel in front and much narrowed behind, the tail bearing four very long hairs, two on each side ; the legs are very long and terminate in a single claw, on each side of which there is a slender hook-like process, so that the end of the legs appears to be split into three parts (hence the name trhingulin which has been applied to this first form of the larva) ; this contrivance enables the little larv^ to cling very tightly to any object. They appear to remain dormant for some time, but under the influence of sufficient warmth exhibit great activity in running over low plants, chiefly those of the Natural Order Ranuncu- lacece. From these they attach themselves to the hairy clothing of bees and other insects which visit the flowers. Such of the larvs as happen to attach themselves to bees of the genus Anthophora are carried by the latter to their nests, where the larva, in the course of a period during which it devours the eggs of the bee and the food stored up by the latter for its own young, changes its form at least three times before it becomes an ordinary beetle pupa from which the perfect oil-beetle emerges. It will be seen that only a very small proportion of the off^spring of the oil-beetle can possibly reach maturity ; and on this point Dr. Sharp says {Cambridge Natural History, vol. vi. p. 274) : ' It is no wonder that the female Meloe produces 5,000 times more eggs than are necessary to continue the species without diminution in the number of its individuals, for the first and most important act in the complex series of this life- history is accomplished by an extremely indiscriminating instinct. The newly-hatched Meloe has to get on to the body of the female of one species of bee ; but it has no discrimination whatever of the kind of object it requires, and as a matter of fact passes with surprising rapidity on to any hairy object that touches it ; hence an enormous majority of the young are wasted by getting on to all sorts of other insects. These larvae have been found in numbers on hairy Coleoptera as well as on flies and bees of wrong kinds. The writer has ascertained by experiment that a camel's-hair brush is as eagerly seized, and passed on to, by the young Meloe as a living insect is.' The oil-beetle cannot fly, and its 112
