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 in 1839 with the exception of the Norman tower. Rawmarsh has large iron-works, steel rolling-mills and potteries, and there are collieries in the neighbourhood. At the time of the Conquest the manor was granted to Walter d’Eyncourt, and in the 12th century it was divided among the three daughters of his tenant Ralph Paganel, who is supposed to have been the founder of the church.

RAWTENSTALL, a municipal borough in the Rossendale parliamentary division of Lancashire, England, 17 m. N. by W. from Manchester by the Lancashire & Yorkshire railway. Pop. (1901) 31,053. This town is a modern creation of the cotton industry; at the beginning of the 19th century it was a secluded village in the wild hilly district of Rossendale Forest. The cotton and woollen industries employ the majority of the inhabitants, and there are stone quarries in the neighbourhood. The town was incorporated in 1891, and the corporation consists of a mayor, 6 aldermen and 18 councillors. Area, 9535 acres.

RAY (Lat. raia). The rays (Batoidei) together with the sharks (Selachoidei) form the suborder Plagiostomi of Elasmobranch fishes, and are divided into six families (see ).


 * . 1.—Pristis perrotteti

The first family, Pristidae, contains only the saw-fishes (Pristis), of which five species are known, from tropical and sub-tropical seas. They frequent especially estuaries and river-mouths, and in some cases make their way over a hundred miles from the sea. Although saw-fishes possess all the essential characteristics of the rays proper, they retain the elongate form of the body of sharks, the tail being excessively muscular and the sole organ of locomotion. The “saw” (fig. 1) is a flat prolongation of the snout, with an endoskeleton which consists of three to five cartilaginous tubes; these are the rostral processes of the cranial cartilage and are found in all rays, though commonly much shorter. The integument of the saw is hard,

covered with shagreen; and a series of strong teeth, sharp in front and flat behind, are embedded in it, in alveolar sockets, on each side. The saw is a formidable weapon of offence, by means of which the fish tears pieces of flesh off the body of its victim, or rips open its abdomen to feed on the intestines. The teeth proper, with which the mouth is armed are extremely small and obtuse, and unsuitable for wounding or seizing animals. Saw-fishes are abundant in the tropics; in their stomachs pieces of intestines and fragments of cuttle-fish have been found. They grow to a large size,

specimens with saws 6 ft. long and 1 ft. broad at the base being common.

The rays of the second family, Rhinobatidae, bear a strong resemblance to the saw-fishes, but lack the saw. Their teeth are consequently more developed, flat, obtuse, and adapted for crushing hard-shelled marine animals. There are about twenty known species, from tropical and subtropical seas.


 * . 2.—Torpedo narce (Mediterranean). A portion of the skin on the left side has been removed to show the electric organ.

The third family, Torpedinidae, includes the electric rays. For the peculiar organ (fig. 2) by which the electricity is produced, see. The fish uses this power voluntarily either to defend itself or to stun or kill the smaller animals on which it feeds. To receive the shock, the object must complete the galvanic circuit by communicating with the fish at two distinct points, either directly or through the medium of some conducting body. The electric currents created in these fishes exercise all the other known powers of electricity: they render the needle magnetic, decompose chemical compounds and emit the spark. The dorsal surface of the electric organ is positive, the ventral negative. Shocks from a large healthy hsh will temporarily paralyse the arms of a strong man. The species of the genus Torpedo are distributed over the coasts of the Atlantic, Pacific and Indian Ocean, and at least one reaches the coasts of Great Britain (T. hebetans). On the west coast of North America T. californica occurs, while on the Atlantic coast there is found the black cramp fish (T. occidentalis). This latter is said to reach a weight of, but such gigantic specimens are scarce, and prefer sandy ground at some distance from the shore, where they are not disturbed by the agitation of the surface-water. Seven genera with about fifteen species have been described, mostly from the warmer seas. All the rays of this family have, like electric fishes generally, a smooth and naked body.

The fourth family, Raiidae, comprises the skates and rays proper, or Raia. More than thirty species are known, chiefly from the temperate seas of both hemispheres, but much more numerously from the northern than the southern. A few species descend to a depth of nearly 600 fathoms, without, however, essentially differing from their surface conveners. Rays, as is