NAUTILUS 



Plate IV. 



Species 3. (Mus. Cuming.) 



Nautilus umdilicatus. Naut. testa suborbiculari, ven- 

 trioosd, striis confer/is spiralibus et coneentricis mi- 

 nute flexuosis, undique granoso-reiiculatd, ad latera 

 mbplanulatd, perampliter spiraliter umbilicatd, mar- 

 ginibus umbilicorum subangulatis ; albidd, rvfescente- 

 ferrugineo postice transversim strigald, strigis suban- 

 gustis, numerous, confertis. 



The umbilicated Nautilus. Shell nearly orbicular, 

 ventricose, granosely reticulated throughout with 

 minutely flexuous spiral and concentric striae, rather 

 rlat at the sides, very largely spirally umbilicated, 

 edges of the umbilicus rather augled ; whitish, pos- 

 riorly transversely streaked with reddish-rust, streaks 

 rather narrow, numerous, close-set. 



Lister, Conch, pi. 552. f. 4. 



Hab. Solomon Islands, New Ireland, etc. 



The shell here figured is that described by Dr. Gould 

 in the Proceedings of the Zoological Society for lv">7. 

 p. 21, as being the best of three observed by him in look- 



ing over the stores of a dealer in Boston, U. S \ 

 differing from the shell commonly kuown as N. urnbili- 

 catus. Having identified it with the original 

 catus of Lister, Dr. Gould proceeds to show that it i> 

 more ventricose, that is to say, broader across than the 

 ordinary form represented in the preceding Plate, with 

 the sides flattened towards the umbilicus, so as to gi\ c a 

 more angular character to the inner excavation and edges 

 of it, whilst the surface is sculptured throughout with a 

 minutely flexuous reticulation of granulated spiral and 

 concentric striae. The painted streaks are, moreover, nar- 

 rower, closer, and of a darker red rust-colour. 



Dr. Macdonald, of H.M.S. Herald, on his return from 

 an expedition among the islands of Western Polynesia, 

 remarked, in a letter to Dr. Bennett, the eminent Aus- 

 tralian naturalist (Pro. Zool. Soc, 1859, p. 22G), " ! hi 

 sculpturing on N. umbilicatus is very distinctly marked on 

 the external surface of the shell, differently from what i- 

 observed either in N. Pompilius or A", macromphalus, ami 

 formins; one of its distinctive characters.'' 



.Tunc, 1861. 



