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Show 52 REl>TILTA. ORDER III. OPHIDIA.(!) Serpents are reptiles without feet, and consequently those which best merit that appellation. Their extremely elongated body moves by means of the folds it forms when in contact with the ground. They are divided into three families. FAMILY I. ANGUINA.(2) The Angues still have an osseous head, teeth, and tongue, similar to those of a Seps; their eye is furnished with three lids, &c., and, in fact, if we may so express it, they are Sepes without feet; they are all comprised in the genus ANGUis, Lin. Characterized externally by imbricated scales, with which they are completely enveloped. They have been separated into four subge· nera; in the three first we still find beneath the skin the bones of the shoulder and pelvis. PsEunoPus, Merr. The tympanum visible externally, and on each side of the anus a small prominence(3) which contains a little bone analogous to the femur, connected with a true pelvis concealed under the skin. The anterior extremity hardly shows itself externally, its only mark be· ing a fold not easily detected; it has no internal humerus. One of its lungs is a fourth less than the other. The scales are square, thick, and semi-imbricate, some of which, between those on the back and those on the belly, being smaller, occasion a longitudinal furrow on each side. (1) Oq>tr, a Serpent. (2) .!lnguis, the Latin generic term for Serpents. (3) Pseudopus, i. e. false foot. I have never been able to discover any division of the extremity of this very small vestige of a foot. M. Schneider has been equally unsuccessful. OPHIDIA. 53 Pallas has described a species of the south of Russia, which is also found in Hungary, and in Dalmatia; the P. Pallaaii, Nob.; Lacerta apoda, Pall. Nov. Com. Petrop. XIX, pl. ix, f. 1; from twelve inches to two feet in length; scales on the back smooth; those on the tail carinated. M. Durville has discovered another in the Archipelago, Ps. Durvillii, Nob., whose dorsal scales are rough and carinate like those on the tail. The 0PHISAURus, Daud.(l) Only differs from the preceding subgenus in the entire deficiency of any external appearance of posterior extremities; the tympanum, however, is still visible, and the scales also form a fold on each side of the body. The small lung is one third as large as the other. The most anciently known species, Oph. ventralis; .llng. ventralis, L., Catesb. II, Iix, is common in the United States. It is of a yellowish-green, spotted with black above; the tail longer than the body; so easily broken that it is commonly termed the Glass-Snake. (2) ANGUis, Cuv. No external appearance whatever of an extremity; the tympanum even being concealed under the skin; the maxillary teeth compressed and hooked, but none in the palate. The body is surrounded with imbricated scales, but has no fold on the side. One of the lungs half the size of the other. One species is very common throughout Europe; .llnguisfragilis, L.; Lacep. II, xix, 1, which has very smooth, shining scales, silve.ry yellow above and blackish beneath; three black lines along the back, which change by age into various series of points, and finally disappear. Its tail is as long as the body, the whole animal being a foot and some inches; it feeds on lumbrici and insects, and produces its young living.(3) These three genera still have an imperfect pelvis, a small sternum, a scapula and clavicle, hidden under the skin. The absence of all these bony parts compels us to separate the subgenus I call (1) From o<jltr a Serpent, and uttvg~f, a Lizard. (2) Add Ophis punctatus,· Oph. striatulus, Nob. two new species. (3) The .!lnguis erix, L. is merely a young specimen of the fragilis, in which the dorsal lines are still well marked; the .11. clivicus, of which Daudin makes an Erix, no one knows why, is an old animal of the same species, with a truncated tail. It is only quoted from Gronovius, who cites the Coluber of Gesner. This Coluber is an oldfragil~. \ |