402 



Messrs. Foorcl and Crick on new and 



sloping sides and rounded edges. Septa rather wide apart, 

 fourteen to a whorl in a specimen whose diameter is 3 inches 

 (fig. 5). Siphuncle a little above the centre in the young 



Fig. 5. 



Nautilus hnnstantonensis. — a, lateral view, showing the open umbilicus ; 

 b, peripheral view, showing the lines of growth. Draw n from a speci- 

 men in the British Museum (no. C. 932), presented by J. E. Lee, 

 Esq., F.G.S. About one half natural size. 



shell, but getting much nearer the peripheral margin in the 

 process of growth, as may be seen in 

 the accompanying section (fig. 5), 

 which is drawn (about three fifths nat. 

 size) from a specimen in the 

 British Museum (no. C. 82449). 

 Surface of the test ornamented with 

 obscure and irregular plications, com- 

 mencing in the umbilicus, where they 

 are most distinct, but becoming less 

 so as they approach the periphery. 

 Fine lines of growth cover the whole 

 of the test. 



BemarJcs. There are two species in 

 the Gault with which the present one 

 may be compared, viz. Nautilus 

 Bouchard ianus, d'Orbigny, and N. 

 MontmoUini, Pictet and Gampiche. 

 Our species agrees with the former of 

 these in the position of its siphuncle, 



but differs in its more numerous septa and larger umbilicus, 

 while it is distinguished from the latter chiefly by the posi- 



