Amphiorus, Verlebrata - Softcover

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1905 Excerpt: ...Proc. Zool. Soc, 1S58. Id. "The Reptiles of British India," London, Ray Society, 1864. G. Jan, "Iconographie generate des Ophidiens," Paris, 1860-82. Lenz, "Schlangenkunde," ed. 2, Gotha, 1870. G. L. Boulenger, "Catalogue of Snakes in the British Museum," London, 1893-6. Huxley, Cope, Zittel, Gadow, op. cit. The skin is scaly, but the scales are purely epidermal structures placed on thickenings of the cutis; osteoderms are absent. The scales vary much in form, number and arrangement. When they are small and overlap they are called scales, but when they are large and only touch by their edges the term shield is applied to them. The scales of the head are distinguished according to their position (Fig. 196). The mental shields (q), i.e. the Bcales in the mental groove on the ventral surface between the rami of the lower jaw, may be mentioned as peculiar to snakes; in front of these two accessory labial shields on either side form with the median labial shield (o) the anterior boundary of the mental groove. The scales on the ventral surface are for the most part broad and invest the body like transverse bands (Fig. 195 6, t), but small scales may also be present here. The ventral surface of the tail, on the other hand, is as a rule, covered by a double, or rarely by a single, row of shields. Snakes moult several times in the course of the year. They strip off the whole of the scaly epidermis. The vertebrae are very numerous and are divided into caudal and precaudal only. All the precaudal vertebrae, except the atlas, carry ribs, and the caudal vertebrae have long transverse processes. The vertebrae are procoelous, the posterior surfaces being hemispherical. The zygapophyses are flat and look dorsally and ventrally and in...