284 
NAUTILOIDEA. 
1881. Nautilus Largilliertianus, Etheridge, in Penning and Jukes- 
Browne’s Geology of the Neighbourhood of Cambridge (Mem. 
Geol. Surv. of Great Britain), Appendix A, p. 151. 
Sp. Ch/ir, Shell compressed at the sides and flattened upon the 
periphery, the latter marked with a slightly raised median line 
(“ normal line ”). Section roughly quadrangular, much higher than 
wide, deeply emarginated by the preceding whorl. Umbilicus 
relatively large aud exposing all the inner whorls. Surface of the 
shell provided only with a few lines of growth, which are not seen 
upon the cast. Septa moderately distant from each other, slightly 
flexuous upon the sides and in the umbilicus, nearly straight in 
passing over the periphery. Siphuucle very near the ventral (inner) 
margin. 
BemarJcs. This shell is readily distinguished from the other Cre- 
taceous species by the squarish form of the whorls, well-defined 
umbilicus, and position of the siphuncle. The lines of growth are 
only seen in well-preserved specimens. 
N. Largilliertianus was found by d’Orbigny in the Craie Glauco- 
nieuse ( = Craie Chloritee of Brongniart, d’Orbigny, &c.) of the hill 
of Sainte-Catherine at Eouen (Seine-Inferieure), associated with 
Ammonites and Turrilites ; also in the lower beds of the Gres Vert 
at Cassis (Bouches-du-Ehone). 
In England the present species is recorded by Sharpe as occurring 
occasionally in the Grey Chalk at Lewes, and in the Chloritic Marl 
of the Isle of Wight ; aud, more common!}’, in the Chalk with 
siliceous grains of Chardstock and Chaldon. 
Horizon. Upper Greensand. Cambridge Greensand. Lower 
Chalk. 
Localities. British. Near Warminster, Wilts (Upper (freeusand) : 
Cambridge (Cambridge Greensand) : Yentnor, Isle of Wight (Chloritic 
Marl) : Sidmouth, Devonshire (Lower Chalk ?). — Foreign. Eouen 
(Seine-Inferieure), France (Upper Greensand). 
Well represented in the Collection. A specimen from Sidmouth, 
Devonshire, was presented by J. E. Lee, Esq., F.S.A., F.G.S. 
[^Nautilus simplex, I. Sowerby, Min. Conch, vol. ii. 1816, p. 47, 
pi. cxxii. — The type of this species cannot be found. It has been 
recorded by Morris, Fitton, Giebel, Mourlon, Ubaghs, aud others, 
but whether correctly or not it is impossible to say. The only 
species from the Upper Greensand which can be fitly compared with 
N. simplex is one described in this volume under the name of Nau- 
tilus semiundatus (see supra, p. 279). The latter, however, is ribbed 
upon the })eriphery, though not on the sides of the shell, whereas 
