EXPLANATION OF PIRATE V. 

 All the figures are from direct photographs of natural size. 



Lecythoconcha lecythis (Benson). 



Fig. I. — Male shell of open- water phase (forma typica) from 

 the central part of the Loktak Lake, Manipur. 



,, 2. — Female shell of the same phase from the same local- 

 ity. 



,, 3. — I^arge shell ( ? a" ) of the marginal phase from the 

 edge of the Loktak Lake, Manipur. 



,, 4. — Exceptionally large shell of the rice-field phase 

 (^ ampuUiforinis, Eydoux and Souleyet) from the 

 Manipur Valley. 



