120 THE ZOOLOGIST. 



NOTICES OF NEW BOOKS. 



The Fauna of British India. Mollusca. — II. (Trochomorphidce- 

 Janellidce). By G. K. Gude, F.Z.S. London, 1914. 

 Taylor & Francis. 



In the present volume of the Molluscan section of the 'Fauna 

 of British India ' the high standard of that unrivalled publication 

 is maintained, both in get-up and matter, while the illustrations 

 are numerous. Although, of course, the book is mainly of 

 interest only to specialist students of Mollusca, and in particular 

 to those concerned with the Land Gastropoda, several facts of 

 general bionomical interest come to light therein. 



Notable is the fact that in the genus Corilla, of the Helicidce, 

 the barrier-armature of the mouth of the shells of the young is 

 invariably different from that of the adult Snails, and especially 

 that in C. adamsi such armature is confined to the young, the 

 adult dispensing with this armature altogether. 



Such a case is curiously paralleled by that of the Madagascar 

 mammal, the Tenrec (Centetes ecaudatus), which is spiny when 

 young, and merely bristly when adult. Another curious parallel 

 between mammals and Snails occurs in the distribution of two 

 Indian forms. Mr. Gude comments on the curious fact that 

 a Snail of the genus Vallonia (V. miserrima) occurs in the 

 Anamulley Hills in Southern India, though the genus is a 

 typically northern one, and none of the other Indian species 

 occur south of the Punjab. Now, among the Goats, typically 

 northern animals, we find that of the two Indian species of the 

 genus Hemitragus, one, the so-called Nilgiri Ibex, is confined to 

 Southern India, far to the south of the haunts of its relative, 

 the Tahr (H. jemlaicus), a well-known Himalayan animal. As 

 the specimens of Vallonia were collected by Colonel Beddome 

 before any European had visited the locality where he obtained 

 them, the possibility of artificial introduction, so potent a factor 

 in the distribution of land Mollusca, is excluded. 



