LECTURE Vin. 
19 
neath, and is much less strikingly tuberculated 
than the Common Sturgeon j being sometimes 
found nearly smooth. It is from the sound or 
air-bladder of this species of Sturgeon that the 
substance called Isinglass is prepared. 
The smallest species of Sturgeon yet known 
is called the Sterlet, which seldom exceeds the 
length of three feet. It is found in the Caspian 
sea, and in some of the Russian rivers, and is 
highly celebrated for the delicacy of its flesh. It 
is recorded of Prince Potemkin of Russia, that 
in seasons when the Sterlet was unusually scarce 
he has been known to give the sum of three hun- 
dred rubles for a tureen of Sterlet soup. The 
Caviar prepared from the roe of the Sterlet is 
a dainty still more expensive, and is said to be 
almost exclusively confined to the use of Russian 
Royalty. 
I shall finish with a very hasty survey of two 
or three other remarkable genera of the Carti- 
laginous tribe. Among these the genus Lophiyts 
claims a place. It has a depressed head, nu- 
merous, sharp teeth, and pectoral fins furnished 
with a kind of joint resembling an elbow. The 
only European species is the L. Piscatorius, or 
