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Serpent

in zoölogy, the ophidia, an order of reptiles popularly distinguished from the rest of the class by having a very elongated body and no external limbs. They are very widely distributed, abounding in the tropics, where they attain their greatest size, absent only from the Arctic and Antarctic regions, and they are mentioned in the earliest records of the human race. The length of the body is a marked feature. The number of vertebræ varies greatly, more than 400 occurring in some of the great pythons.

No sacrum exists, and there is no distinction between or divisions of the spine into cervical, dorsal, and lumbar vertebræ. A notable feature is the large number of ribs; almost all the vertebræ, with the exception of the atlas or first, bearing these. The ribs articulate with the transverse processes of the vertebræ, and are not attached inferiorly to any breastbone, but are imbedded in cartilages which are in turn connected with the great scales or scuta that cover the ventral surface of the body. The premaxillæ are represented usually by a single small bone, which rarely has teeth, and is joined to the maxillæ by fibrous tissue only. The floor of the skull is flat, while in front it diminishes greatly in height. The hyoid is very rudimentary, and is represented by two cartilaginous filaments, unconnected in any way with the skull. In the pythons a pair of rudimentary hind limbs exists, and traces of a pelvis are also found. ented usually 1 Locomotion is effected by the muscular contractions of the body, the animals moving literally on the ends of their ribs.

Teeth are borne by the premaxillary bones, by the maxillaries, palatine, and pterygoid bones, and by the dentary part of the mandible. One of the most singular developments of teeth in serpents and indeed in the entire animal kingdom, QCcurs in a little African snake-Rachiodon. In this snake, the ordinary teeth are very small, but the lower or inferior spines of some eight or nine vertebræ of the neck are long, and their enameled tips project into the interior of the gullet, so that when the snake swallows an egg, the brittle morsel passes entire into the gullet, and is broken only when fairly on its way into the stomach. The teeth of serpents are not implanted in sockets, but become ossified to the surfaces of the! bones which bear them. They are replaced when worn away or injured by new teeth developed at the bases of the former ones. In the typically poisonous serpent (e.g., the rattlesnake) the upper jaw bears two largely developed teeth termed fangs. Each fang has a very deep groove running down its anterior aspect, and the margins of this groove SERPENTINE are opposed so as to convert it into a canal-hence the fangs are said to be canal opens by a wide aperture above into the poison gland, so that by the compression, muscular and friable, of the gland , the poison flows down the canal and is ejected, through the into the wound made by the fang.

The poison of different serpents varies in intensity and virulence, but appears to take effect on the blood.

The most effective treatment for snake-bite is to tightly round the limb, above the wound, and to excise the part freely, and then to suck the blood rethe parts deeply before removing the ligature. In sucking a poisoned wound ing a poisoned wound, the danger conwound in the mouth by which the poison may be absorbed.

The digestive system of serpents presents nothing worthy of special remark, save that the intestine ends in a cloaca opening transversely. There is no urinary bladder, and the heart (as in all reptiles save the Crocodilia) is three-chambered.

Serpents are divided into three groups: viperine, the last two groups possessing poison fangs, the boas, which kill their prey by constriction, belonging to the first. serpents are oviparous, the venomous are ovoviviformer deposit the eggs in a long string in some heap of decaying vegetable matter , and leave them; them; while some of the larger serpents by the heat of their bodies. Some of the innocuous kinds are capable of being tamed; ; the rat snake (Ptyas mucosus) is often kept in houses in India for for the purpose of destroying rats and mice.