,346 NAUTILUS 



unguiculatus. 18. Shell diaphanous, minute, 

 with seven joints protuberant at the dissepi- 

 ments, and six conical tubercles. 



Nautilus unguiculatus. Gmelin, p. 3372. 



Spengler Schr. Dan. Ges. i. p. 373. t. 2. f. 9 d. 

 Inhabits sands in India. Gmelin, 

 Shell minute, thin, shining, white, polished, and slightly 



ribbed. 



•A* TV* 



Elongated and almost straight. 



semilituus. 19. Shell incurved, and spiral at the 

 summit, with the whirls contiguous. 



Nautilus semilituus. Linnceus Syst. Nat. p. 1163. Schroe- 

 ter Einleitung, i. p. 14. Gmelin, p. 3372. Montagu 

 Test. p. 196. Maton and Racket, in Lin. Trans, viii. 

 p. 118. 



Nautilus Lituus. Schreber Conch, i. p. 6. 



Nautilus subarcuatulus. Walkers Minute Shells, p. 3. f. 73. 

 Adams's Micros, p. 642. t. 14. f. 38. Montagu Supp. 

 p. 80. t. 19. f. 1. 



Plancus, t. 1. f. 10. Martini, i. t. 20. f. 186 and 187. 

 Inhabits the shores of Liburni. Linnaus. Sandy shores of 



Sandwich and Sheppy Islands. Boys. 

 Shell minute, brown, with the summit rolled in, something like 



a Crozier ; joints convex ; aperture, with a small produced 



syphon. 



lituus. 20. Shell sub-conical, with globular joints 

 becoming gradually smaller; summit incurv- 

 ed and spiral. 



Nautilus Lituus. Gmelin, p. 3372. 

 Spengler Schr. Dan. Ges. i. p. 373. t. 2. f. 10, d tog. 

 Klein Danz. Naturf. Ges. Schr. ii. p. 47. t. 1. f. a. 

 Inhabits the Red Sea, and is frequently found among fossils. 

 Gmelin. 



carinatulus. 21. Shell oblong, keeled; aperture 



narrow oval. 



Nautilus carinatulus. Walker's Minute Shells, t. 3. f. 72. 



Adams's Microsc. p. 642. t. 14. f. 37. Montagu Test. 



p. 195. Maton and Racket, in Lin. Trans, viii. p. 118. 



