SECTION X. 183 



upper part or head is narrow, turns fpiral- 

 ly, and is like the flern ; the reft of it 

 widens to the other end, is quite hollow, 

 forms a horizontal aperture, and lies lower 

 than the flern or fpiral end. 



The fpecies of this family are very few, 

 not above three or four. And thqfe knowu 

 are brownifli or whitifli, and thin almoft 

 as paper, whence they have obtained the 

 name they bear of Paper NautilL 



Thefe Shells have by mod authors beeu 

 ranl^ed with the common Nautili, by the 

 name of Nautili Vacui, on account of their 

 failing i but it is evident, that in flrufture 

 they have not the leaft affinity to one an- 

 other. 



Gualtieri has made them a different ge^ 

 nus, and named it Cymbium, which name 

 I have adopted. Linnasus alfo makes it a 

 diftinft genus, and calls it Argonauta. 



N4 It 



