SERINGAPATAM 346 SERPENT other; a sequence. In mathematics, a number of arithmetical or algebraic terms in succession, increasing or diminishing according to a certain law. Series derive their names from the laws which govern the formation of their respective terms. Thus, an arithmetical series is one whose consecutive terms have a common differ- ence; a harmonic series one of which every three successive terms are in a harmonic proportion. A geometric series is one every term of which has a constant ratio to the preceding one; it belongs to the family of recurring series, in which each term is a constant function of one or more preceding terms. In botany, a row or layer; in botanical classification, a grade intermediate be- tween a class and an order. In chemistry, a group of compounds, each containing the same radical. Thus the hydrocarbon, CH4, methane, may take up any number of the molecules of the radical CHo, thereby giving rise to the series C^Ho, ethane, C3H8, propane, C4H10, quartane, etc. In geology a term for subdivisions of sedimentary strata. SERINGAPATAM (properly, Sri- ranga-pa-tana, "city of Vishnu"), a celebrated town and fortress in the prov- ince of Mysore, Madras presidency, India. It is on an island formed by two branches of the Kaveri, 245 miles S. W. of Madras, and is generally ill-built, with narrow, dirty streets. It was once the capital of Mysore. The palace, formerly extensive, is now in ruins. Other notable public buildings are the great mosque, and the pagoda of Sri Ranga, the arsenal and the cannon foundry. The massive forti- fications were the work of Tippoo, the son of Hyder Ali, assisted by French engineers, and the fortress was three times besieged by the British, first in 1791, and afterward in 1792 and 1799. On the last occasion it was carried by assault, Tippoo himself being slain while fighting desperately, together with 8,000 men. Pop. about 12,500. SEROUS FLUIDS, a name given to the lymph-like pellucid fluids secreted by certain membranes and contained in cer- tain cavities of the body. An excess of this secretion constitutes a diseased and often a dropsical condition. SEROUS MEMBRANE, in anatomy, a membrane having its surface moistened by serum. They line the cavities of the body from which there is no outlet. The chief are the peritoneum, the two pleurae, the pericardium, and the arachnoid mem- brane. Serous membranes differ from mucous membranes in having thinner layers, finer fiber, and an epithelium with only a single layer of polygonal cells. SERPENT, in zoology, 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 at- tain 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 vertebra? varies greatly, more than 400 occurring in some of the great pythons. No sacrum exists, and there is no dis- tinction between or divisions of the spine into cervical, dorsal, and lumbar verte- bra?. A notable feature is the large num- ber of ribs; almost all the vertebrae, with the exception of the atlas or first, bear- ing these. The ribs articulate with the transverse processes of the vertebra?, and are not attached inferiorly to any breast- bone, 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 premaxillae are represented usually by a single small bone, which rarely has teeth, and is joined to the maxilla? 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, uncon- nected in any way with the skull. In the pythons a pair of rudimentary hind limbs exists, and traces of a pelvis are also found. 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 singu- lar developments of teeth in serpents and indeed in the entire animal kingdom, oc- curs 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 vertebra? of the neck are long, and their enameled tips project into the interior of the gullet, se that when the snake swallows an egg, the brittle morsel passes entire into the gul- let, and is broken only when fairly on its way into the stomach. The teeth of ser- pents are not implanted in sockets, but become ossified to the surfaces of the bones which bear them. They are re- placed 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
