11 



ON PHILALANKA, A NEW SUBGENUS OF ENBODONTA, WITH 

 DESCRIPTIONS OF TWO NEW SPECIES FROM THE INDIAN 

 REGION. 



By Lieut.-Colonel H. H. Godwin-Atjstew, F.R.S., F.Z.S., etc. 



Read IQth December, 1897. 



PLATE I. 



Among' the sub-provinces into wliicli the Molkiscan fauna of the 

 Indian region may be divided, the island of Ceylon is conspicuous 

 for the many very distinct genera and species which have been found 

 there, and which have not as yet been discovered elsewhere save in 

 the neighbourhood of the gneissic mass of the Mlgiris. It is an 

 indication that this region is one having a former history of its own, 

 connecting it in some way with an area and a fauna of greater extent 

 than at present, both of which were long ago diminished. It presents 

 a field for speculation as to what the conditions were which enabled 

 that land to receive its moUuscan inhabitants and which finally 

 restricted them to their present limited range. It is not a new 

 subject for thought, because Mr. W. T. Blanford, so long ago as 1876, 

 wrote an excellent paper in the Annals and Magazine of Natural 

 History, entitled " The African Element in the Fauna of India," with 

 a criticism of Mr. Wallace's views. 



The present paper does not permit of entering into a subject of 

 this nature ; but I may point to the occurrence of such genera as 

 Acavus, Gorilla, Catmdus, and Aulopoma, that, as well as a more 

 extended acqaintance with the indigenous HelicidsB, tends to support 

 the same interesting fact in distribution. 



The species I first describe is another instance of a similarly isolated 

 genus, which I place in the family Endodontidse. The genitalia in 

 very few species of that family are known, and since this one 

 cannot be placed in any of the subgenera mentioned by Pilsbry in 

 his Manual of Conchology, I have considered it necessary to establish 

 a new subgenus for these Indian forms, which I name Philalanka, 

 from "Lank" or "Lanka," the well-known name for Ceylon, 



Philalanka, n.subgen. 



Jaw composed of numerous squarish plates. Basal plates of teeth 

 of the radula square or oblong ; central teeth tricuspid, laterals multi- 

 cuspid. No mucous gland at extremity of the foot. Generative organs 

 simple. No amatorial organ and no accessory organs. Shell small, 

 many-whorled, pyramidal or trochiform with a single liration, 

 unicoloured. 



1. Philalanka secessa, n.sp. PI. I, Figs. 1-5. 



Shell (Figs. 1, \d) pyramidal, base convex, narrowly umbilicated. 

 Sculpture : fine, irregular, costulate transverse lines ; a single lirate 



