CLASS PISCES. 589 



muzzle, is small and devoid of teeth ; the palatine 

 bone is cemented to the maxillaries, and we find the 

 intermaxillaries in a rudimentary state, in the thick- 

 ness of the lips ; supported on a pedicle with three 

 articulations, this mouth is more protractile than that 

 of the squali ; their eyes and nostrils are at the sides 

 of the head ; some barbels depend from the muzzle. 

 The labyrinth is entire in the bone of the cranium, 

 but there is no vestige of an external ear ; a hole 

 pierced behind the temple is only the vent which con- 

 ducts to the gills. The dorsal is behind the ventrals, 

 and the anal is under it. The caudal surrounds the 

 extremity of the spine, and has a salient tube under- 

 neath, shorter, however, than its principal point. In- 

 ternally, we find the spiral valve of the intestine and 

 the pancreas united into a mass, as in the selacii ; but 

 there is, moreover, a very large natatory bladder, 

 communicating by a wide hole, with the oesophagus. 



The sturgeons ascend in abundance from the sea 

 into certain rivers, where they constitute very pro- 

 fitable fisheries. Most of their species have well- 

 flavoured flesh. Caviar is made of their eggs, and 

 isinglass of their natatory bladder, 



We have in western Europe, 



Acipenser sturio, L., Bl. 88. (the common stur- 

 geon). Six or seven feet long, with pointed muzzle ; 

 its bucklers, disposed in five ranges, are strong and 

 spiny. It flesh is rather similar to that of veal. 



The rivers which discharge themselves into the 

 Black sea, and into the Caspian, produce, with our 



