40 Records of the Indian Museum. [Vol. VI, 



margin sloping posteriorly ; ventral margin very gently rounded ; 

 anterior side somewhat angularly rounded ; posterior side truncate. 



Long. . . . . . . 5 mm. 



Lat. . . . . . . 8 , , 



Hab. — Rambha, vS. end of Lake Chilka (Dr. N. Annandale) : 

 on stones between tide marks. Type in Indian Museum, Calcutta. 

 (M. -^-y-B.) 



Corhicula triheniensis , sp. nov. 



Shell ovately subtrigonal, somewhat inflated, dark brownish 

 olive; umboes rather large, prominent, iridescent ; dorsal margin 

 arched ; ventral margin gently rounded ; anterior side acumi- 

 natel3^ rounded ; posterior side angled above, almost truncate 

 below^; both valves very finely and closely striate, covered with a 

 shghtly laminiferous periostracum. 



1 



Fig. 3. — Corbicula triheniensis, sp^ nov. 



Long. . . . . . . 8-5 mm. 



Lat. .. .. .. 10-5 ,, 



Hab. — Tribeni, near Calcutta (B. L. Chaudhuri) : on the edge 

 of the river. Type in Indian Museum, Calcutta. (M. » V".) 



Modiola annandalei, sp. nov. 



Fig. 4. — Modiola annandalei, sp. nov. 



Shell narrow, curvedly oblong, moderately solid, anteriorly 

 olive, posteriorly dark green, both valves marked with concentric 

 grow^th lines and sculptured at the anterior extremity and pos- 

 teriorly with indistinct but fairly regular costulae and markedly 

 angled from the umboes to the posterior side ; umboes small, 

 stained with purple, very anteriorly situate ; dorsal margin 

 sloping, very slightly arched; ventral margin curved, excavated; 



