236 PISCES. 



ACIPENSER, Lin.(l) 



The general form of the Sturgeon is similar to that of the Shark, but the 

 body is more or less covered with bony plates in longitudinal rows; the ex- 

 terior portion of the head is also well mailed; the mouth, placed under the 

 snout, is small and edentated; the palatine, soldered to the maxillaries, con- 

 verts them into the ( upper jaw, and vestiges of the intermaxillaries are found 

 in the thickness of the lips. This mouth, placed on a pedicle that has three 

 articulations, is more protractile than that of a Shark. The eyes and nostrils 

 are on the side of the head, and cirri are inserted under the snout. The 

 labyrinth is perfectly formed in the cranial bone, but there is no vestige of 

 an external ear. A hole perforated behind the temple is a mere spiracle, 

 which leads to the branchiae. 



The Sturgeon ascends certain rivers in great numbers, and is the object of 

 important fisheries; the flesh of most species is agreeable, their ova are con- 

 verted into caviar, and their natatory bladder into isinglass. Western Eu- 

 rope produces 



.5. ruthenus, L. (The Sterlet.) Seldom more than two feet in length; 

 plates of the lateral rows more numerous and carinated, those of the belly 

 flat. It is considered a delicious fish, and its caviar is reserved for the 

 Russian court. There is reason to believe that it is the Elops and the JLd- 

 penser, so highly celebrated among the ancients. 



A. huso, L. (The great Sturgeon. ) Blunter plates and a shorter snout 

 and cirri than those of the Common Sturgeon; the skin also is smoother. 

 It is frequently found to exceed twelve and fifteen feet in length, and to 

 weigh more than twelve hundred pounds. One specimen was captured 

 whose weight amounted to near three thousand pounds. The flesh is not 

 much esteemed, and is sometimes unwholesome; but the finest isinglass is 

 made from its natatory bladder. It is also found in the Po. North America 

 has several species of this genus which are peculiar to it. 



SPATULARIA, Sh. 



These fishes are recognized at once by the enormous prolongation of their 

 snout, to which its broad borders give the fignre of a leaf. Their general 

 form and the position of their fins remind the observer of a Sturgeon, but 

 their gills are still more open, and the operculum is prolonged into a mem- 

 branous point which extends to near the middle of the body. The mouth 

 is well cleft and furnished with numerous small teeth. 



But a single species is known, the Paddle-fish of the Mississippi. 



CHIMJERA, Lin. 



The Chimaerae are closely allied to the Sharks in their general form and in 

 the position of their fins, but all their branchiae open externally by a single 



(1) Adpenser is the ancient name; Sturio, whence Sturgeon, is modern, 

 and is probably the German name Stoer latinized. 



