RAY (OF. raie, carte, Fr. role, from Lat, raja, ray, roach; connected with AS. reohhc. LGer. ruche, Ger. Roche, SlDutc•h roch, OF. roche,rosse. Fr. roche, Eng. roach). A general name for the elasmobranch fishes of the order Batoidei, char acterized by the dorso-ventrally flattened body. This order includes the saw-fishes. sea-devils, stingrays, skates, guitar-fishes, and torpedoes (qq.v.). The true rays have a flat body: the pectoral fins are large and fleshy. appearing as lateral expansions of the body, and along with it forming a circular disk or a rhomboid, to which is attached a rather long and slender tail. The pectoral fins are prolonged till they meet in front of the snout, and backward till they join the ventral fins. The eyes and spiracles look upward. The gill-openings (five) are on the under side of the body, close behind the mouth; and toward the tail are the stomach, intestine, and other viscera. The males are furnished with claspers. Most of the species are egg-laying; but the guitar-fishes (Rhinobatidre) are pecu liar in that their eggs are retained until they hatch within the body. The eggs are large and are inclosed in thin horny cases resembling those of sharks• but more rectangular in form, with projections at each of the four corners, by which they catch upon and are held to eel-grass or other supports until they hatch. These eggs are familiarly known in England as 'skate bar rows,' and in America as 'mermaids' purses.' Rays are found in all seas, especially in the warmer ones. and commonly inhabit sandy or muddy shores, lying on the bottom, where they feed on mollusks and are often cast up on the beach.
The most common rays in the United States are those of the typical family Rajidw, usually called 'skates.' Those of the family Myliobatidic are called 'eagle-rays' (q.v.). A large section of the order is known as the suborder Mastieura, or whip-tailed rays, in allusion to the very long slender tail, which in most species, especially of the family Dasyatidie, is armed, near its base, by one or more large jagged, erectile spines• capable of inflieting a severe and even dangerous wound. This has given to those fishes the name
of sting-ray. The common sting-ray of the At lantic shore is the 'clam-craeker' (Dasyntis ccn trara). which abounds from to Cape Hat teras. and sometimes reaches a length of ten to twelve feet. The color is olive-brown above and nearly white below. Until half grown the young are smooth. but as they approach maturity broad conical bucklers appear on the back and tail, and many flattened tubercles. This tendency to grow rough with age characterizes most of these fishes, but is sometimes checked. as in the case of the smooth sting-ray or 'bat-fishe (Myliobatis Californiens) of the Pacific Coast. Sting-rays gather upon beds of cultivated oysters, or in places where clams abound, and destroy great numbers of these valuable mollusks. No of any poison glands has been found• hut Kings ley says that the mucus of the fish probably pos sesses poisonous qualities.
Fossil selachinnA allied to the rays are repre sented by fragmentary remains from Devonian and Carboniferous rocks and by more perfect and abundant material in the and Tertiary deposits. Exquisitely preserved skeletons of Rhinobatis from the Jurassic lithographic stone of Bavaria present few differences from modern species of the same genus. Consult: Kingsley, Standard Natural History (Boston• 18S5) Goode• Fishery Industries. sec. i. (Washington, 1884) ; Jordan and Evermann, American Food and Game Fishes (New York, 1902). See Plate of RAYS AND SKATES.