The microscope and its revelations . hesionperfect.* And this view of the case derives confirmation, fromthe presence of a similar apparatus, on a far larger scale, onthe foot of the Dj/tiscus (Fig. 295, a). The first joints of thetarsus of this insect are widely expanded, so as to form anearly-circular plate; and this is provided with a very re-markable apparatus of suckers, of which one disk (a) isextremely large, and is furnished with strong radiating fibres,a second (b) is a smaller one formed on the same plan (athird, of the like kind, being often present), whilst the greaternumber are co
The microscope and its revelations . hesionperfect.* And this view of the case derives confirmation, fromthe presence of a similar apparatus, on a far larger scale, onthe foot of the Dj/tiscus (Fig. 295, a). The first joints of thetarsus of this insect are widely expanded, so as to form anearly-circular plate; and this is provided with a very re-markable apparatus of suckers, of which one disk (a) isextremely large, and is furnished with strong radiating fibres,a second (b) is a smaller one formed on the same plan (athird, of the like kind, being often present), whilst the greaternumber are comparatively-small tubular club-shaped bodies,each having a very delicate membranous sucker at its ex-tremity, as seen on a larger scale at e. These last seem to * See Mr. Hepworths communications to the Quaxt. Joum. of , vol. M., p. 158, and voL iii., p. 312. 678 TINTSECTS M^D AHACHKIDA. resemble the hairs of the Flys foot in every particular butdimension; and an intermediate size is presented by the hairs Fig. A, Foot of Dytiscus, showing its apparatus of suckers; a, b, largesuckers; c, ordinary suckers:—b, one of the ordinary suckers morehighly magnified. of many beetles, especially Curcnlionidse.—The feet of Cater-pillars differ considerably from those of perfect Insects. Thoseof the first three segments, which are afterwards to bereplaced by true legs, are furnished with strong horny claws;but each of those of the other segments, which are termedpro-legs, is composed of a circular series of comparativelyslender curved booklets, by which the caterpillar is enabled toelmg to the minute roughnesses of the surface of the leaves,&c., on which it feeds. This structure is well seen in the pro-legs of the common Silk-worm. 398. Stings and Ovipositors.—The Insects of the orderHymenoptera are all distinguished by the prolongation of thelast segment of the abdomen into a peculiar organ, which, inone division of the order, is a sting, and in the other is an
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