EXPLANATION OF PI, ATE II. 



All figures are direct photographs of dry shells. 



Margaritanopsis laosensis (Lea). 



Figs. 1-4. — Shells of various ages, forming the type-series of 

 Unio sella, Tapparone-Canefri : x£. 



Margaritanopsis sp. 

 Fig. 5. — Type-shell of Unio rectangularis, Tapparone-Canefri : 



Parreyssia houngdaranicus (Tapparone-Canefri). 



Fig. 6. — Type-shell from Houngdaran River, Burma : natural 

 size. 



Parreyssia feae (Tapparone-Canefri). 



Fig. 7. — Adult shell from Meetan, Burma: natural size. 

 ,, 8. — Type shell from the same locality: natural size. 



Lamellidens corrianus (Lea). 



Fig. 9. — Type-shell of Unio protensus, Tapparone-Canefri : 

 Xf 



„ 10. — Type-shell of Unio protensus var. elliplicus, Tap- 

 parone-Canefri: x£. 



,, 11. — Type-shell of Unio dolichorhynchus, Tapparone- 

 Canefri: x£. 



Lamellidens generosus (Gould). 



Fig. 12. — Young shell of L. marginalis subsp. sawaddyensis , 



Preston: x£. 

 ,, 13. — Specimen identified as Unio marginalis var. tricolor 



by Tapparone-Canefri : X \. 

 ,, 14. — Half-grown specimen of L. marginalis subsp. 



sawaddyensis, Preston: x£. 

 „ 15. — Type-shell of Unio pulcher, Tapparone-Canefri: 



XJ. 

 „ 16. — A shell identified by Preston as L. marginalis var. 



sublamellata : X £. 

 „ 17. — Type-shell of L. marginalis subsp. sawaddayensis, 



Preston : x£. 



