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Show ~52 tated edges; of a quadrifid lip( I), of which the two lateral d'. visions are the large t, and tra~sversely annulated, res~ntblin1 the membranous feet of caterp1l1ars; of two pal pi or little fe; united at base and unguiculated at the extr·emity, and 0 ; ~ second lip(2) formed by a second pair of feet, dilated d . q urnted at base, and terminated by a stout movable hook wh m'f eir'w r extrem.ity. fi d 'ose IS per orate by a hole which affords an issue to a venomous fluid. The body is depressed and membranous. Each of its rings is covered with a coriaceous or cartilaginous plate, and most generally bears but a single pair of feet(3) ; the last is usually thrown backwards, and elongated into a kind of tail. The organs of respiration are wholly or partly composed of tubular trachere. . These animals run very fast, are carnivorous, avoid the hght, and conceal themselves under stones, logs, in the ground, &c. They are much dreaded by the inhabitants of hot climates, where they are very large, and where their venom is possibly m?re active. The Scolopendra morsitans is styled In the Antilles the malfaisante. Some of them exhibit phosphorescent properties. The organs of generation are internal and placed at the ~ 1~ A part analogous to the lower lip of the Chilognatha, representing, in my ?Ptnlon, t!1e tongue of the Crustacea, but also capable of fulfilling the function o( Jaws; Sav1gny calls it the first auxiliary lip. (2) The second auxiliary lip of the same naturalist. It is not annexed to the head, but to the antl!rior extremity of the first semi-segment. The two hooked feet, by t~e union and dilatation of their first joint, form a plate resembling a men· tum and l1p. The same segment bears the two first ordinary feet. In the Scolopendt ·a: proper of Leach, the two first stigmata are situated under the third half· segment, the fil'St not counted; the second and following one will compose the first complete ring, and then the two first stigmata are found, as in other Insects, placed 011 a space corresponding to the prothorax. This second auxiliary lip may thu~ represent the inferior lip of the grinding Hexapoda. But here the pharynx ts P!~ced ~efore that lip, whl!reas in the lfyriapoda it is situated before the first auxJ!Jary hp. It is from these considerations and affinities and from others furnished by the Entomostraca and Arachnides, that I consider' the feet of the Hexapoda as analogous to the six foot-jaws of the Crustacea Decapoda· (3) In this case they ape but semi-annuli. See our general observations on the order. MYH.IAPODA. 253 osterior extremity of the body, as in most of the following insect& The stigmata are lateral or dorsal, and more appa-ent than in the preceding family. r The Chilopoda, which, in the system of Leach, form the order Syngnatha, from these last characters, the nature of the respiratory organs and the feet, may be thus divided: Some have but fifteen pairs of feet( 1 ), and their body viewed from above presents fewer segments than when seen from beneath. ScuTIGERA, Lam.-Cermatia, Illig. The body covered with eight scutelliform plates, under each o£ which M. Marcel de Serres has observed two pneumatic sacs or vesicular trachere, which receive air and communicate with lateral and inferior tubular trachere. The under part of the body is divided into fifteen semi-annuli, each bearing a pair of feet, terminated by a very long slender multi-articulated tarsus; the last pairs are more elongated; the eyes large and compound. Their antennre are slender and tolerably long; the two pal pi salient and furnished with small spines. The body is shorter than in the other genera of the same family, and the joints of their feet are proportionably longer. The Scutigerre, which by these characters form the passage from the preceding family to the present one, are extremely agile animals, and frequently part with some of' their feet when seized. The species found in France(2) conceals itself between the beams and rafters of houses. LtTHOBius, Leach. The stigmata lateral; body divided above and beneath into a similar number of segments, each bearing a pair of feet; the superior plates alternately longer and shorter, and overlapping each other close to the extremity. L. forficatus; Scolopendraforficata, L.; Fab., De Geer; Geoff., (1) Dr Leach makes two pairs more by including the palpi and the hook-like feet of the head. (2) The Scolapendre a vingt-ltuit pattes of Geoffroy which appears to differ from the 8. ccleoptrata, Panz., Faun. Insect. Germ., L, xii, :mel from that of Linn~us;lulJU araneoidea, Pall., Spicil. Zool., JX, iv, 16;-Scolopendra longicornia, Fab • of Tranquebar. See also Leach, Zoo!. Miscell., Oermatia livida, CXXXVI, and Lin. Trans. XIV. |