MOLLUSC A or INDIA. » 



in the South, extending to Ceylon, a few species being found 

 common on both sides. It has been studied by H. A. PiLsbry, 

 who cites 58 species ; G. K. Gude, in Paun. Erit. India, raised the 

 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 determinations. 



The subgenus Rishetia docs not extend to South India, appa- 

 rently. Ueddome has recorded B. t<'vuispi.i-n from North Canara, 

 based only on a single specimen without any history: see what I 

 say of this under the title of Jowjisjnra 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 

 llev. Stephen Hislop, in the ' Proceedings ' of the Geological 

 Society, 1859, p. 154, describes the "Tertiary Deposits associated 

 with Trap-liock in the East Indies," and the fossil shells are 

 described and figured by him. Having very recently received 

 through Dr. N. Annandale a 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 frceliwater shells 

 to Mr. Benson, the highest authority on the Molluscs of our 

 Indian lakes, and he gives it as his opinion that not one of the 

 specimens submitted to him exactly corre8])onds to anything he 

 has seen." This was written 60 years ago ; it is in accordance 

 with my conclusions expressed in a letter to Dr. Annandale 

 dated 31st 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 I'reshwater 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 moUuscau life from the far South. Perhaps no moi'e interesting 

 history can be recalled than my finding on Shengorh Peak, 7000 feet, 

 in the Diitla Hills, a species I named and described as Staffordia 

 daflaensis, Moll. Ind. pt. x. April 1907, p. 184, pi. cxiii. In 

 expectation of receiving other material, I did not refer to my 

 description of Biakia striata, var., from Siam, in Proc. Malacolog. 

 Society, vol. vii. pt. 2, p. 93, pi. x. June 1906. There is no doubt 



* In a paper on some Fresljwater Fossils from Central South Africa (Annals 

 & Mag. Nat. Hist., vol. v. Jlaroh 1920) Mr. R, Bidlen 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 Mysorellu of 

 Southern India, pointing out the uecessUy for their generic revisiou. 



