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Show 244 I SBCTA. In the eighth or the NEUR~PTEJL<\, there. are six legs, four membranous and _naked wmgs, and. mandibles and jaws for mastication; the Wings are finely reticulated, and the in· ferior are usually as large as the superior, or more extended in one of their diameters. In the ninth or the H VM:ENOPTEHA, there are six feet, and four membranous and naked wings, and mandibles and jaws for mastication; the inferior wings are smaller than the others , and the abdomen of the female is almost always terminated by a tcrebra or sting. In the tenth or the LEPIDOPTERA, there are six legs, four membranous wings, covered with small coloured scales resembling dust; a horny production in the form of an epau· Jette, and directed backwards, is inserted before each upper wing, and the jaws are replaced by two united tubular fila· ments, forming a kind of spirally convoluted tongue( I). In the eleventh or the RHIPIPTERA, there are six legs, two membranous wings folded like a fan, and two crustaceous mo· Table bodies, resembling little elytra(2), situated at the ante. rior extremity of the thorax ; the organs of manducation are simple, setaceous jaws, with two pal pi. In the twelfth or the DIPTERA, there are six legs, two mem· , branous extended wings, accompanied, in most of them, by two movable bodies or l}alteres, placed behind them; the or. gans of manducation are a sucker composed of a variable num· ber of setre, inclosed in an inarticulated sheath, most frequently in the form of a proboscis terminated by two lips . . (1) Spiritrompe. See our general observations on the class. The thorax of the Lepidoptera has more analogy with that of the Neuroptera, than with that of the Hymenoptera, the segment which I have called the mediate appearing to form part of the abdomen, while in the latter and in the Diptera it is incorporated with the thorax. (2) Formed, as we presume, by pieces analogous to the epaulette or pterygoda of the Lepidoptera. 'MYRIAPODA. 245 , ORDER I. MYRIAPODA( 1 ). The Myriapoda commonly called Centipedes, are the only animals of this class which have more than six feet in their perfect state, and whose abdomen is not distinct from the trunk. Their body, destitute of wings, is composed of a (usually) numerous suite of annuli, most commonly equal, each of which, a few of the first excepted, bears two pairs of feet mostly terminated by a single hook; these annuli are either entire or divided into two demi-segments, each bearing a pair of those organs, and one of them only exhibiting two stigmata(2). The Myriapoda in general resemble little Serpents or N ereides, their feet being closely approximated to each other throughout the whole extent of the body. The form of. these organs even extends to the parts of the mouth. The mandibles are hi-articulated and immediately followed by a quadrifid piece in the form of a lip with articulated divisions, resembling little feet, which, from its position, corresponds to the ligula of the Crustacea; next come two pairs of little feet, the second of which, in several, resemble large hooks, that appear to replace the four jaws of the last mentioned animals, or the two jaws as well as the lower lip of Insects: they are a sort of buccal feet. The a~tennre, two in number, are short, somewhat thicker towards the extremity, or nearly filiform and composed of seven joints in some; in others they are numerous and setaceous. Their visual organs are usually composed of a union of ocelli, and if in others they present a cornea (1) The Mitosata, Fab. (2) The annuli of the body of Insects are usually provided with two stigmata. If those of the Scolopendrre, part:cularly the larger species, those which have twenty.one pairs of feet, be thus considered, it will be found that they are alternately destitute of, and provided with, two stigmata, and that thus, compared with these latter animals, they are in fact but semi-annuli. Each complete segment will then have two pairs of feet, one of which is supernumerary, since, in other Insects, the annuli furnished with feet have but two. |