EXPLANATION OF PLATE III. 



Fig. 13. — Neosolen aquae-dulcioris , side view, X 2. 

 ,, 14. — A^. aquae-dulcions , side view, X 2. 

 „ 15. — Animal of CuUellus subellipticus, Dunker, side view, 



X 3- 

 „ 16. — Alimentary canal of C. subelhpticus. 

 „ 17. — Ventral view oi A zor coarctatus, X 2. 

 ,, 18. — Animal of A. coarctatus, side view, X i. 

 „ 19. — Animal of A. coarctatus, side view, X 2, 

 „ 20. — Novaculina gangetica, Benson, ventral view, X 2. 

 ,, 21. — N. gangetica, Benson, side view (animal), X 2. 



,, 22. — N. gangetica, Benson, side view (animal), X 2. 

 Mantle lobe of one side removed. 



„ 23. — N. gangetica, Benson, alimentary canal (diagram- 

 matic). 



