336 ARGONAUTA. 



Inhabits the East Indies. Favanne. 



1 he length of the shell is near an inch and a half, and its height 

 when placed on the keel scarcely exceeds half an inch ; the 

 aperture widens from the keel till it attains the width of 

 about thirteen lines, and then turns almost at right angles 

 towards the spire. Martini has represented a horn-like ap- 

 pendage at each of the angular extremities of the aperture, 

 similar to those of Argonauta Gondola, but he has arranged 

 it as a separate species. 



viirea. 6. Shell conical, compressed, transversely- 

 ribbed; keel convex, toothed. 



Argonauta vitreus. Gmelin, p. 3368. 



Patella cristata. Linnaus Syst. Nat. p. 1160. Schroeter 



Einl. ii. p. 421. Gmelin, p. 3710. 

 Argonauta, No. 1. Schroeter Einl. i. p. 6. 

 Carinaria vitrea. Lamarck Syst. des Animaux, p. 99. 

 Le grand Nautile vitre. Favanne, i. p. 719. t. 7. f. C 2. 

 Argenville Zoom. t. 10. f. B. Martini, i. p. 239. t. 18. 

 f. 163. 



Inhabits Amboyna, extremely rare. Favanne. 



Shell about two inches long, and nearly equally broad at the 

 aperture, rather conical, with the sides compressed and trans- 

 versely ribbed. The summit is rolled in, and forms a very 

 small external wheel, like that of Patella Hungarica. 

 From the summit along the back of the spire to the base, 

 runs a convex keel which has the appearance of being denti- 

 culated, from the crossings of the transverse ribs. There 

 can be no doubt that this is the P. cristata of Linnaeus, and 

 it has much more affinity with the present Genus than 

 Patella. 



cymbium. 7. Shell with its keel wrinkled and with- 

 out teeth. 



Argonauta Cymbium. Linnaus Syst. Nat. p. 1161. Mar- 

 tini, i. p. 238. 1. 18. f. 161 and 162. Schroeter Einl. i. 

 p. 5. Gmelin, p. 3368. 



Le petit Nautile vitre. Favanne, i. p. 718. t. 7. f. C 1. 



Gualter, t. 12. f. D. 

 Inhabits the Mediterranean. Linntzus. 

 Shell small, not so large as Patella mitnda, which in shape it 



somewhat resembles, compressed, slender, transversely 



wrinkled, and longitudinally striated; summit obtuse, and 



slightly recurved. 



