NAUTILUS. 341 



LiEviGATULUS. G. Shell spiral, smooth ; joints ten, 

 with the partitions slightly elevated ; aperture 

 triangular. 



Nautilus laevigatulus. Walker Min. Shells, t. 3. f. 67. 

 Adams's Micros. 2nd. Ed. p. 641. t. 14. f. 32. Montagu, 

 p. 188, and Supp. p. 75. t. 18. f. 7 and 8. Maton and 

 Racket, in Lin. Trans, viii. p. Ho. 

 Inhabits the sea at Sandwich and Seasalter in Kent. Walker. 

 Shell minute, opake, smooth, pale ferruginous brown, with ten 

 flexuous rays of rather a darker colour, and but slightly ele- 

 vated at the partitions : differs from N. rot at us in being ra- 

 ther larger, and having more celis, as well as in its colour, 

 and not having a regular keel. 



depressulus. 7. Shell spiral, much compressed, 

 with about nine joints, and a small pellucid 

 spot in the center. 



Nautilus depressulus. Walker's Minute Shells, t. 3. f. 68. 



Adams's Miscros. p. 641. t. 14. f. 33. Montagu Test. 



p. 190. Supp, p. 78. t. 18. f. 9- Maton and Racket, in 



Lin. Trans, viii. p. 115. 

 Inhabits the sandy shore at Reculver in Kent. Walker. 

 Shell extremely minute, not half so large as N. rotatus, from 

 which it also differs in being much more compressed, in 

 having no keel, and in the greater number of its joints; co- 

 lour white, glossy, semi-pellucid, with the partitions marked 

 by their opacity, but not at all raised. Mr. Montagu says, 

 that the central spot is not an umbilicus. 



crispus. 8. Shell spiral, with contiguous whirls, 

 and the joints crenated ; aperture semicor- 

 date. 



Nautilus crispus. Lin. Syst. Nat. p. 1162. Martini, i. 

 p. 250. t. 20. f. 172 to 174. Schroeter Eiul. i. p. 10. 

 Gmelin, p. 3370. Walkers Min. Shells, t. 3. f. 65. 

 Adams's Micros, p. 640. t. 14. f. 30. Fichtel and Moll, 

 t. 4. f. d, e,f. Montagu Test. p. 187. t. 18. f. 5. Ma- 

 ton and Racket, in Lin Trans, viii. p. 115. Dorset 

 Cat. p. 42. 1. 19. f- 29. 

 Le Nautile microscopique granuleux. Favanne, i. p. 728. 



t. 7. f. B 1, and t. 69. f. D 2. 

 Plancus, 1. 1. f. 2. Gualter, 1. 19- f. A, D. 

 Inhabits the Mediterranean. Linnaus. Shores of Great Bri- 

 tain, not unfrequent. Montagu. 



