78 NAUTILUS. 



tant of the Nautilus, as the shape of the shell will 

 indicate, possesses the power of floating on the sur- 

 face of the sea, but is uiore frequently found re- 

 versed, and bearing his boat upon his back. The 

 animal of the Nautilus spirula possesses a con- 

 formation analogous to that of the Cuttle-fish, and 

 in the posterior extremity of his body he bears the 

 shell, which is only partially uncovered. This ani- 

 mal was brought from New Holland by M. Peron. 

 It has been presumed that other concamerated 

 shells are similarly situated, and that they serve 

 merely to protect a small portion of the animal 

 with their exterior chamber. 



No exemplification is given of the divi.sion C, 

 because all the shells which it contains are either 

 minute or fossil, neither of which come within 

 the design of a work merely elementary, and con- 

 fined to recent subjects. Fossil conthology, though 

 subject to the same arrangement, is well worthy 

 of a separate consideration. 



To vavTiXoc, a sailor J this genus evidently owes 

 its appellation. 



