254 ON THE CLASSES OF THE 



the parts ; it will at least be interesting to inquire briefly 

 whether because the Cephalopoda have no direct con- 

 nexion with the fishes, they must therefore haven6ne with 

 any others of the vertebrated animals. 



For this purpose let us commence with the eye. The 

 iris of this is of a golden colour in the Cephalopoda, in rep- 

 tiles and in fishes. Naturalists have observed that there is a 

 vestige of three eyelids in the Sepia, which we know only 

 to be the case with the reptiles among the Vertebruta. 

 The third eyehd is semitransparent in both reptiles and 

 Cephalopoda, and is placed behind. The granulated 

 glandular lobes behind the eyes are also common to both. 

 The closed ear with the cavity of the tympanum nearly sphe- 

 rical, and its single trumpet-shaped ossiculum, is an imper- 

 fect sketch of that of the Chelonian reptiles. The semi- 

 circular canals are wanting in the Cuttlefish. In the 

 tortoises they exist, but are I'emarkably short. Daudin has 

 observed that of all the senses of reptiles, to judge from 

 the simple structure of the nostrils, that of smelling must 

 be the most imperfect; and Cuvier says, that he was un- 

 able to recognise any part specially constructed for this 

 purpose in the Cephalopoda, though he adds that they ap- 

 pear to enjoy this sense, since they are known to be at- 

 tracted by the odour of different substances. The coria- 

 ceous skin of the Sepia is very analogous to that of the 

 soft tortoises. So much for the organs of sense. 



Now if we proceed to consider the internal structure, 

 and particularly the organs of digestion, the convex, hooked 

 and sharp-pointed horny mandibles of the Sepi<z will be 

 seen to inclose a tongue which, ft'om its cartilaginous cover- 

 ing of transverse laminae and projectile nature, necessarily 

 calls to our recollection that of many reptiles. Like those of 



