Page:Jardine Naturalist's library Entomology.djvu/123

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ENTOMOLOGY.
117

the coxa or hip, which is received into an acetabulum or socket, where it is suspended by a ligament. Frequently it is of a globular form, more or less surrounded and enclosed by a horny substance; at other times it forms a truncated cone, and appears attached to the thorax by the greater part of its base. When of the former shape, its motions are free and versatile; when of the latter, they are more restricted. In intimate connection with the coxa, but capable of independent movement, is a small piece named the trochanter. Its form is subject to many changes, but it is most commonly triangular or quadrangular, often prolonged into a lateral point. It articulates with the coxa, sometimes by ball-joints entering corresponding sockets, or simply by a membrane, the latter being generally the case when the shape is annular, as among the Diptera. Its union with the succeeding part of the leg, namely the thigh (femur), is usually much closer. The thigh, in far the greater number of instances, is the largest and most conspicuous joint of the leg. It is usually thick and robust; in form cylindrical, or compressed; straight, or arched; slender at the base, and incrassated at the middle or apex, &c. Sometimes the anterior thighs are longest and thickest, (Acrocinus longimanus, Nat. Lib. Coleop. pl. 21, fig. 1,) occasionally the middle pair (Onitis), and in all the saltatorial tribes, and many besides which do not leap, the hinder pair are greatly enlarged, (Haltica, Locusta, Sagra). The thighs are less frequently furnished with foliaceous and other appendages than that part of the leg next to be