262 
XArTILOTDEA. 
1878. Nautilus Bouchardianus, Lintli, Beitrage ziir geol. Karte der 
Schweiz, Lief. xiii. p. 21. 
? 1879. Nautilus Bouchardianus, II. B. Medlicott and W. T. Blanford, 
Manual of the Geology of India, pt. i. p. 284. 
Sp. Char. Shell ranch inflated, especially in the adult, nearly as 
wide as high, smooth, with only a few lines of growth, and a little 
stronger in some jflaces ; strongly rounded on the periphery. Um- 
bilicus open, generally very small, but sometimes a little wider. 
Septa moderately distant, slightly sinuous. Siphuncle small, 
situated a very little above the centre. 
Bemarlcs. Among the globular species of Cretaceous Xautili, the 
only one that can bo strictly compared with N. Bouchardianus is 
N. IcBvigatus, which is, however, less inflated and has more distant 
septa than the first-named. A7 Clementinus is distinguished from 
the present species by its more compressed form and by the position 
of its sij)huncle. 
Stoliczka^ regards the Indian species of Bouchardianus (Blan- 
ford) as divisible into three species, viz. : — • 
1. Nautilus Bouchardianus, d’Orbigny, var. 
2. Nautilus sjiJuericus, Forbes. 
3. Nautilus suhlcevigatus, d’Orbigny, var. 
The first (1) he regards as a variety of N. Bouchardianus, and 
observes that “ the siphon is in one specimen [in the Indian Col- 
lections] distinctly external and in another internally subcentral. 
M. Pictet does not mention an internal position of the siphuncle in 
any of the European specimens. As, however, these specimens do 
not differ in any other characters from each other and from the 
true European Gault fossil, I retain them provisionally as varieties 
of N. Bouchardianus, d’Orb.” Of the second species (2) he remarks 
that he has no doubt, from specimens in the Madras Museum, that 
it is the true N. sphcericus of Forbes, and he points out that the 
character distinguishing it from N. Bouchardianus consists in the 
^'‘globosity (not the thickness) of the shell,” as Forbes^ correctly 
concluded in his description of the species. Upon the third species 
(3) Stoliczka observes tflat the specimens representing it (which 
were figured by Blanford '^ under the name N. Bouchardianus) are 
^ Mem.Geol. Surv. of India — Palaeont. ludica — i. Cretaceous Cephalopoda of 
Southern India, 1865, p. 203. 
^ Trans. Geol. Soc. 1846, ser, ii. vol. rii. p. 98. 
^ Mem. Geol. Surv. of India — Palaeont. Indica — i. Cret. Ceph. of Southern 
ndia, 1861, p. 13, pis. iii., iv., v. 
