Records of the Geological Survey of India. 
[vol. i. 
■ M' 
Of the M URIC IBM 1 would particularly mention Pottia Pondicherriensis, because it so 
much recalls the form of our common, recent Pollia melanostoma, and a species belonging 
to the genus Troption. 
The TRITomiDX have representatives in species belonging to Hindsia, Triionium and 
Lagena ; the buccieidje in those of Nassa and Pscudoliva ; the pukpuridx in Indicia, 
numerous species of Pupa and one of Rapana. Not less interesting are also two species of 
Triehot-ropis and five species of the CANCMLLARIIDM, representing the genera Oancellaria, 
Euclia and Narona. No terebridje have occurred, and the pt&AMIDELI.id/E offer no 
peculiarities, nor are they very rich in species or genera. 
The ceritiiiid/e mostly belong to marine sub-generic types, the absence of the very 
large number of POTAmmitJE, occurring in the deposits of the Alpine-Gosau formation, being 
remarkably conspicuous as one of the most important differences between the two faunas. 
The same applies to the MEIANIIO.K. their absence in Southern India being equally due to 
the apparent want of brackish or fresh water deposits, so far as they are known at the present. 
The TURlUTliLllOX have yielded five forms identical with European ones, T. midtistriata 
being probably the best known, T. nerinea, nodosa, affinis and Neptv.ni. The rest of the 
species peculiar to the Indian deposits do not differ in general character from European types. 
Of the SCAltVJE three out of four are identical with European species. Of the VERMEtidje 
two interesting species have been referred to a new genus Tnbulostium, being very charac¬ 
teristic for the Ootatoor beds, which are the lowest of the series. Of the littorinidjE , the 
occurrence of which in cretaceous rocks was always disputed, six different species have been 
met with. Of the RISSOIDX I may draw attention to two rather large species of Rissoa, 
one smooth Rissoina and three species of that peculiar genus Keilogtoma, differing from 
Rissoina by the great thickness of the apertural margins. The katicidje are characterized 
by the usual large number of species belonging to the genus Euspira \ three genera, 
Naticina, Velutina and Amplostoma of the VELUtinidje also deserve specially to be noticed. 
When speaking of the family neritidje, the UMBOnhoje, tubbinidje and trochid a 
& e., I had occasion to remark that most of the recent so called sub-generic forms are already 
to be found during the cretaceous period. Some of the generic types ore very interesting 
and new to the fauna, as, for instance, Ft dates; Teinostoma and F'itrinel/a ; Oxytele. 
Gibbula, Eurheltts, Cantlwridus, Sfc. 
Tlie ElEUROTOMARUDJE arc not very varied in genera, but one species of the peculiar type 
Leplomaria (L. indica), is very common, occurring almost through all the successive groups 
from the lowest to the highest; it greatly resembles several of the European forms. 
The Opisthobbakcitta arc also worthy of notice, being represented by 24 species; 
these belong to Actaonina (2), Actceon (0), Trochactmon (3), Bullina, (2), Bnllinula 
(1), Arellano, (4), Rintjinclla, (l), Bingictda (2), Eupiycha (3) and Cytiehna (1). This un¬ 
usually large number of species of that sub-order is the more interesting, as the recent species are 
far from common shells. The genera Trochactceon, Avdlana , Rsngmella and Euptycha 
arc chiefly cretaceous forms, and therefore in comparison with the present fauna of very 
great importance. Aottzonina is one of the oldest genera, but I believe there are a good 
number of species of recent shells which ought to be transferred to that genus. Of the 
EENTALllD.v., being the only representatives of the Pkosococephaia, merely four species of 
the genera, DentaHum, Antale and Fustiaria (n. gen.) were recorded. 
After this general review of the fauna I may now rater upon the distribution of the 
species in the different groups which, beginning with the lowest, are the Ootatoor, Trichi- 
nopoly and Arrialoor in the Trichinopoly district, and the Yaludayur and Yerdaehelhim 
groups near Pondicherry. These last two are equivalent to the first and third named one, 
respectively. Geological details respecting these groups and their fauna will he found in 
Mr. H. E. Blanibrd's Report in the IVth Volume of the Memoirs of the Geological Survey 
of India. The present remarks regarding the distribution of tlio species of Gastropoda will 
therefore be very general. 
The 237 species of Gastropoda, described from the cretaceous deposits of South India, 
divide themselves into the different groups, thus: 113 species are peculiar to the Arrialoor 
group, 59 to the Trichinopoly and 3(5 to the Ootatoor; 20 species are common to the 
Trichinopoly and Arrialoor groups, 4 to the Ootatoor and Trichinopoly, none, however, with 
sufficient certainty to the Ootatoor and Arrialoor solely. Only five species, Fulgurttria elongata , 
