MM. Foord and Crick — On Nautilus elegans, Sby. 551 



Nautilus pseudoelegans, d'Orbigny. 



1840. Nautilus pseudoelegans. d'Orbigny, Paleontologie Franchise (Terrains Cretaces), 



tome i. p. 70, pi. viii., pi. ix. 

 1853. Nautilus pseudoelegans, Sharpe, Description of the Fossil Remains of Mollusca 



found in the Chalk of England (Mon. Pal. Soc), pt. i. Cephalopoda, p. 13, 



pi. iv. figs. 2(7, '2b. 



1858. Nautilus pseudoelegans, Pillet, Description Geologique des Environs d'Aix en 



Savoie, p. 33, pi. vi. fig. 3. 



1859. Nautilus pseudoelegans, Pictet et Campiche, Description des Fossiles des 



Environs de Sainte-Croix (Paleontologie Suisse, ser. ii. pt. i. livr. vii.), p. 



123, pi. xiv. and xiv. bis. 

 ? 1861. Nautilus pseudoelegans, Blanford, Mem. Geol. Surv. of India — Palseont. 



Indica — I. Cretaceous Cephalopoda of Southern India, p. 33, pi. xvii. fig. 3; 



pi. xviii. figs. 3, 3a, ob ; pi. xix. ; pi xx. figs. 1, la. 

 ? 1866. Nautilus pseudoelegans, Stoliczka, ibid. p. 210, pi. xciii. fig. 3. 



Fig. 3. 



Nautilus pseudoelegans. — a, lateral view, showing three of the septa, and the cast of 

 the body-chamber, partly covered by the test ; b, peripheral view, showing the 

 curvature of the septa in the median line. Drawn from a specimen in the 

 d Orbigny Collection in the Museum of Natural History, Paris. About one- 

 third natural size. 1 



Specific Characters. — Shell much inflated, very broad, with some- 

 what flattened sides and a very broadly rounded periphery, slightly 

 flattened in the adult shell. Greatest width of the whorls about 

 midway between the umbilicus and the median line of the periphery. 

 Umbilicus small but distinct. Aperture very wide, semi-lunate, 

 with rounded lateral margins. Septa approximate, very slightly 

 sinuous on the sides of the shell, and forming an inconspicuous sinus 

 on the periphery. Siphuncle situated below the centre of the septa. 

 Test in the young shell very slightly striated transversely, but in the 

 adult covered with very strong, regular, prominent, separate ribs or 

 plications, which form a sigmoid curve on the sides of the shell, and 



1 A cast of this specimen is now in the British Museum. 



