PPtEFACK 



^ision of MoUusfcs 

 Sectional Library 



The Indian Molluscan Fauna has for a great number of 

 }'ears attracted the attention of many collectors and zoologists, 

 foremost among whom may be mentioned the following : 

 Benson, Pfeiffer, Stoliczka, Nevill, Theobald, Hanley, the 

 two Blanford brothers, Beddome — unfortunately none of 

 these any longer with us — and Lt.-Col. Godwin- Austen. 

 The last named has an intimate and extensive knowledge of 

 the Indian Mollusca, both conchological and anatomical, 

 equalled by no man living. Of the total number of 572 

 species of land operculates known from India, (Jeylon, and 

 Burma, no fewer than 170 have been named and described 

 by him, the next highest number — 85 — standing to the credit 

 of Benson, while W. H. Blanford is res})onsible for G4, 

 Pfeiffer following with -42, and Beddome with 25. In the 

 largest genus — Ali/avus, containing 145 known Indian 

 species — Godwin-Austen is credited with as many as 102. 



The classification adopted in the present volume is mainlv 

 that proposed by Kobelt in " Das Tierreich," Lief. K!. 



In the marine operculates breatiiing is effected b}' means 

 of one or two branchijc. The terrestrial forms, however, 

 having adopted an aerial mode of life and consequentlv 

 breathing air instead of water, their resj)iration is carried on, 

 as in the Pulmonata, by a lung formed from the mantle- 

 cavity. In some genera, where the shell is completely closed 

 by the operculum, a tube has been develo])ed on the last 

 whorl, near the aperture, for the purpose of admitting air 

 into the shell. >Sucli are : Al/fcrns, Pteroc//clus, Oj'isthopoms, 

 Spiracuhan, and Rldostonia. \x\ the last genus the anterior 



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