MOLLUSCA OF INDIA. 9 
in the South, extending to Ceylon, a few seed being found 
common on bout sides. It has been studied Dye AL. ‘Pilsbry, 
who cites 58 species; G. K. Gude, in Faun. Brit. India, raised tho 
number to 80; Colonel R. H. Beddome (1906) gives 53; while 
Nevill in his Proof Copy ‘ Hand-list’ (1881) records 65. 
The species are very distinct; none are found outside the 
Peninsula, as far as my investigations go, and I have been 
able to correct several incorrect t determinations. 
The subgenus Risuetia does not extend to South India, appa- 
rently. Beddome has recorded 2. tenwispira from North Canara, 
based only on a single specimen without any Rien: : see what I 
say of this under the title of longispira No. 2, Sikhim and the 
Teesta valley. 
Going back in time, it has not been recorded from the Inter- 
trappean beds of the Peninsula—those of Nagpur, for instance ; 
but I see no reason why it should not be found in them, especially 
the smaller species, and it should be looked for. We do not 
half know the genera preserved in this old formation*. The 
tev. Stephen Hislop, in the ‘Proceedings’ of the Geological 
Society, 1859, p. 154, describes the “ Tertiary Deposits associated 
with Trap- Rock in the East Indies,” and the fossil shells are 
described and figured by him. Having very recently received 
through Dr. N. meendales collection of these fossils from Nagpur, 
I have been led to read the paper. An interesting paragraph 
I quote from is on p. 164:—‘* I have shown my freshwater shells 
to Mr. Benson, the highest authority on the Molluses of our 
Indian lakes, and he gives it as his opinion that not one of the 
specimens submitted to him exactly corresponds to anything he 
has seen.” ‘his was written 60 years ago; it is in accordance 
with my conclusions expressed in a letter to Dr. Annandale 
dated 3lst March, 1920: **I have had an hour’s look at them, 
and can say they are all unknown forms to me.” This rich 
fauna of Upper Cretaceous age should no longer lie thus neglected, 
for since Hislop wrote an enormous advance has been made in our 
knowledge and treatment of the Land and Freshwater Mollusca. 
“The Zoological Results of the Abor Expedition, 1911-12.” 
published in the ‘ Records Indian Museum,’ vol. viii., have con- 
siderably modified our ideas of distribution and led to the records of 
the past (nearly forgotten) being looked up. It points to a migration 
of mollusean life from the far South. Perhaps no more interesting 
history can be recalled than my finding on Shengorh Peak, 7000 feet, 
in the Dafla Hills, a species I named and described as Staffordia 
daflaensis, Moll. Ind. pt. x. April 1907, p. 184, pl. exiii. In 
expectation of receiving other material, I did not refer to my 
description of Diakia striata, var., from Siam, in Proc. Malacolog. 
Society, vol. vil. pt. 2, p. 93, pl. x. June 1906. There is no doubt 
* In a paper on some Freshwater Fossils from Central South Africa (Annals 
& Mag. Nat. Hist., vol. v. March 1920) Mr. R. Bullen Newton on p. 246 refers 
to certain species in the Nagpur beds. Also my contribution in “ Records of 
two Indian Museums” 1919, Oct. vol. xvi. pt. vi. on the genus Mysorella of 
Southern India, pointing out the necessity for their generic revision. 
