1922] B. Prashad : Burmese Vnionidae. 99 



sub generic names have recently been introduced by Haas. Prob- 

 ably my new name may have to be dropped when the exact 

 generic positions of the various subgenera of Haas can be decided 

 by examination of the animals of these species. 



The soft parts of this genus were described by me in 1919 l as 

 those of Psendodon, s.s., based on an examination of the animal of 

 P. salwenianus. 



Indopseudodon salwenianus (Gould). 



18 (.4. Anodon salwenianus, Gould, op cit., p. i6o. 



1914. Psendodon salwenianus, Simpson, op. cit., pp. 1093, 1094. 



1915. Psendodon salwenianus, Preston, op. cit., p. 152. 



1919. Psendodon salwenianus, Prashad, op. cit., pp. 295, 296, fig. 6 



(animal). 



1920. Psendodon salwenianus, Haas, op. cit., pp. 341, 342, pi. xliii, 



fig. 4. 



I. salwenianus, as Simpson pointed out in his description of 

 the species, is distinguished from the allied species by its consider- 

 able length and by the strong plicated sculpture on the posterior 

 wing. 



In the Indian Museum collection it is represented bj' a fair 

 series of specimens from the Tenasserim River and a shell with 

 the label " Burma ," exact localit\' not stated. No specimens of 

 this species were obtained by Fea. 



Indopseudodon ava (Theobald). 



1873. Monocondylaea avae, Theobald, Journ. As.Soc. Bengal, XI. I!, 



pt. ii, p. 209, pi. xvii, fig. 15. 

 1900. Psendodon ava, Simpson, op. cit., p. 839. 



1914. Psendodon ava, Simpson, op. cit., p. 1098. 



1915. Psendodon ava, Preston, op. cit. pp. 153, 154. 



1920. Psendodon avae, Haas, op. cit., p. 343, pi. xliii, figs. 5, 6. 



Simpson in his first work included this species in his section 

 Binereus of the genus Psendodon, but in his recent ' Catalogue ' 

 was doubtful as to its exact position though he still retained 

 it in this section. Haas, however, from an examination of an 

 authentic Burmese specimen was able to assign the species to its 

 exact position near 7. salwenianus. I have before me one of Theo- 

 bald's specimens from Mandalay and can confirm Haas' conclu- 

 sions. Theobald's comparison of this species with cumingi and 

 inosculans in the remarks at the end of his description is rather 

 unfortunate as the species is not related to either of them. 



Genus Parreyssia Conrad. 



1914. Parreysia, Simpson, op. cit., pp. 1 103, 1104. 

 1919. Parreysia, Prashad, op. cit., p. 292, fig. 3. 



Eight species of this genus are now known from Burma. Of 

 these only P. smaragdites occurs in Assam as well, all the others 



1 Prashad, Rec.lnd. Mus. XVI, pp. 293, 196, fig. 6 ( 1919) 



