. The Cambridge natural history. Zoology. xvin CHONDROSTEI 493 species, but the exact number is uncertain. Sturgeons are abundant in the Black Sea, the Sea of Azov, the Caspian, and their tribu- tary rivers, notably the Danube, Don, Dnieper, Ural, and Volga. They are also present in the rivers and on the coasts of Northern Europe and of China. Five species occur in North America, on the Atlantic and Pacific coasts, and in the rivers of these regions as well as in the Great ' One or two species are almost exclusively fresh-water, but most Sturgeons are migratory Fishes, living in the sea
. The Cambridge natural history. Zoology. xvin CHONDROSTEI 493 species, but the exact number is uncertain. Sturgeons are abundant in the Black Sea, the Sea of Azov, the Caspian, and their tribu- tary rivers, notably the Danube, Don, Dnieper, Ural, and Volga. They are also present in the rivers and on the coasts of Northern Europe and of China. Five species occur in North America, on the Atlantic and Pacific coasts, and in the rivers of these regions as well as in the Great ' One or two species are almost exclusively fresh-water, but most Sturgeons are migratory Fishes, living in the sea, but ascending rivers for spawning. Their food consists of worms, molluscs, the smaller Fishes and aquatic plants; and in feeding the mouth is protruded downwards in the form of a cylindrical, spout-like structure and thrust into the mud. The only species certainly known to frequent the British. Fig. 290.—The Sterlet {Acipenser ruthemis). 0, Barbels ; , caudal fin ; , dorsal fin ;, pectoral fin \, pelvic fin ; sc, scutes ; «./, ventral or anal fin. (From Parker and Haswell, after Cuvier.) coasts is the common Sturgeon {A. shirio), which is also found in the Black Sea and the Mediterranean, and is abundant on the Atlantic coast of North America from Maine to South Carolina. The species occurs all round our coasts, more plentifully, perhaps, on the northern and eastern shores. In the spring and summer the Fish ascends the rivers, often to a considerable distance. Its presence has been recorded in the Severn, near Shrewsbury; in the Trent at Nottingham, and also, but not in recent years, in the Thames above London Bridge.^ In this country the species is a " Eoyal Fish," and by an unrepealed Act of Edward II. it is enacted that " the King shall have the wreck of the sea through- out the realm. Whales and Great Sturgeons, except in certain places privileged by the ; ^ If not so large as some of its Eussian relatives, A. sturio often attain
Size: 3416px × 732px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectzoology, bookyear1895
