BY THE REV. J. E. TENISON-WOODS. 
1005 
looking through a large collection with every gradation of shape 
and colour between one species and another, one cannot help being 
struck with the slender evidence on which some species rest. One 
i.s inclined to say that the species are comparative!}^ few, but the 
variations are great in extent and endless in number. 
Nevertheless, there are certain peculiar genera which stamp a 
character on the region, besides certain abnormal species. The 
facies of the region is Indian. All traces of African influences 
have disappeared. There is no Achatina, few Pupas, whilst 
Cyclostoma is beginning to take a subordinate place. Amongst 
the Cyclophoridae we find peculiar though wide-spread types \ and 
amongst the Helicidse unmistakable uniformity. The individuals 
have all marked characters, so that a small amount of experience 
suffices to enable us to tell at a glance whether any individual 
shell is a member of the Malayan fauna. 
There are in the region we are dealing with about 380 known 
species or varieties of land-shells divisible into the following 
genera : — Streptaxis, E)inea, Vitrina, Helicarion, Nanina, Troclio- 
nanina, Ilyalinia, Trocliomorp)ha, Fatula, Helix, Cochlostyla, 
Bulimus, Bulimina, Stenogyra, Rhodina, Glessula, Pupa, Hypse- 
lostoma, Clausilia, Cyclotus, Opisihoporus, Pterocyclos, Sjyiraculum, 
Cyclophorus, Leptopoma, Alycctus, Diplommatina, Opisthostoma, 
PupiTia, Megalomastoma, Uyhocystis, Georissa. Of these the dominant 
genera are Nanina, Helix, Cyclophomis, Bulimus, and Clausilia. 
And this is the ca.se in the Indian fauna. Thei’e is in fact the 
strongest resemblance between the relative proportion of certain 
genera in the two provinces ; the difference being the complete 
disappearncc from the Malayan Peninsula of AcJmtina and some 
other African genera. The large j>redominance of forms of Helix 
resembles India almost to the very number of species. The peculiar 
form of Vitrina distinguished as Nanina, but with slender claims 
to a generic j)Osition, is a feature shared by Ceylon, and to some 
ext<‘nt by the Philippine Islands. Nanina is a thin, dopre.ss(‘d, 
uinbilicated shell, with a keel at the periphery, highly j)olishcd and 
with a tendency to bi-partite colouring. 
