348 



ARGONAUT, OR PAPER-NAUTILUS. 



chambered, as in the true Nautilus ; but possesses one spiral 

 cavity, into which the animal can withdraw itself entirely. The 



FIG. 646 ARGONAUT, OB PAPER-NAUTILUS. 



animal, however, has no muscular attachment to its shell ; whence 

 it has been supposed by many Naturalists to be a parasitic in- 

 habitant, which had taken up its abode within it ; the shell, 

 from its resemblance to that of the Carinaria (Fig. 682) being 



