

226 PISCES. 



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 converted 

 into caviar, and their natatory bladder into isinglass. Western Europe produces 



A. ruthenus, Lin. (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 Acipenser, so 

 highly celebrated among the ancients. 



A. hvso, Lin. (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, Shaw. 



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

 snout, to which its broad borders give the figure 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. 



CJIIM/KKA, Linnceus. 



The Chimserffi 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 

 apparent hole on each side, although if we penetrate more deeply, we find that 

 they are attached by a large part of their edges, and that in fact there are five 

 particular holes terminating in the bottom of the common aperture. A vestige 

 of an operculum, however, is concealed under the skin. The jaws are still 

 more reduced than in the Shark, for the palatine and tympanic bones are also 

 mere vestiges suspended to the sides of the snout, and the vomer is the only 

 representative of the upper jaw. Hard and indivisible plates supply the place 

 of teeth, four on the upper jaw and two on the lower. The snout, supported 

 like that of a Shark, projects forwards, and is pierced with pores arranged in 

 tolerably regular lines ; the first dorsal, armed with a strong spine, is placed 

 over the pectorals. They produce very large coriaceous eggs with flattened 

 and hairy borders. 



C. monstrosa, Lin. (The Arctic Chimera.) Two or three feet long, of a sil- 

 very colour, and spotted with brown. From the Northern and European seas. 



