ARGONAUTA. 337 



cornu. 8. Shell with the whirls detached, and the 

 aperture somewhat four-sided. 



Argonauta Cornu. Gmelin, p. 3368. 

 Argonauta, No. 2. Schroeter Einleitung, i. p. 6. 

 Le Comet de chasseur. Favanne, i. p. 665. t. 5. f. I. 

 Chemnitz, x. p. 4. t. 137. f. 1271 to 1273. 



Inhabits the Cape of Good Hope. Gmelin. 



Shell near half an inch in diameter, and the aperture, which is 

 much dilated, is rather more than half as broad ; the whirls 

 are revolute, and detached from each other in the same man- 

 ner as those of Nautilus Spirula, and are marked with trans- 

 verse striae, and on the side of the keel with a longitudinal 

 groove. Favanne has placed this species among the Ser- 

 pulce. 



arctica. 9. Shell perforated with the keel entire. 



Argonauta Arctica. Fabricius Fauna Grxnlandica, p. 386. 

 Gmelin, p. 3368. 



Clio helecina. Pallas Spic. Zoologica, fasc. x. p. 38. 

 Inhabits the Greenland Seas, on which it floats in spring and 



autumn. Fabricius. 

 Shell about three and a half lines in diameter, very brittle, 



white, finely grooved, and the umbilicus perforated. 



VOL. I. 



