1922.] B. Prashad: Burmese Unionidae. 107 



such as L. corrianus are not enough to warrant the erection of a 

 distinct variety, much less a separate species. 



L. corrianus like L . marginalis, is widely distributed through- 

 out India and Burma. 



Lamellidens jenkinsianus subsp. obesa (Hanley and 



Theobald). 



1920. Lamellidens jenkinsianus subsp. obesa, Prashad, Rec. Ind. 

 Mus. XIX. pp. 170-172, pi. ix, figs. 1, 2. 



In the paper cited above I have recently discussed the 

 question of the various forms of L. jenkinsianus. In Pea's 

 collection from Burma there is a young specimen of the form 

 obesa from Tonghoo. This specimen is one of the few unnamed 

 specimens of Fea's collection and only had the name ' Unio ' on 

 the label. The specimen is from the same locality from which 

 Theobald's specimens, now in the Indian Museum, were collected. 



It may also be noted here that the specimens referred to as 

 Unio marginalis var. obesus by Tapparone-Canefri (loc. cit., p. 346) 

 are, as has been pointed out already, only typical specimens of 

 L, marginalis. 



Lamellidens generosus (Gould). 

 PI. II, figs. 12-17. 



1847. Unio generosus, Gould, op. cit., p. 220. 



1870. Margaron (Unio) generosus, Lea, Synonyms, p. 20. 



1876. Unto generosus and var. angustior, id., ib., p. 22, pi. xlvi, figs. 



4. 7- • , 



1876. Unio lamellatus, var. (nee I.ea), Hanley and Tlieobald, op. cit., 



p. 5, pi. ix, fig. 6. 

 1889. Unio marginalis var. zonata (nee Hanley and Theobald), 1 var. 



tricolor (nee Kiistcr), U. pulcher and var. lamellatiformis, 



U . generosus and var. delapsus, Tapparone-Canefri, op. cit., 



pp. 346, 347, 350, 351,352. 



1899. Unio generosus, von Martens, op. cit.. p. 46. 



1900. Lamellidens generosus, Simpson, op. cit., p. 857. 



1912. Lamellidens marginalis subsp. sawaddyensis, Preston, Rec. Ind. 

 Mus. VII, p. 305. 



1914. Lamellidens marginalis var. tricolor and subsp. sawaddyensis, 



L. Burmanus * and L. generosus, Simpson, op. cit., pp. 1168, 

 1 169. 1170, 1 175. 



1915. Lamellidens marginalis var. tricolor and subsp. sawaddyensis, 

 and L. pulcher with var. lamellatiformis, Preston, op. cit., pp. 

 176, 177, 185. 



The above elaborate synonymy is based on a careful examina- 

 tion of the type-specimens of Tapparone-Canefri's and Preston's 

 new species and also of authentic specimens of others in the 

 Indian Museum collection. 



The specimens identified by both Tapparone-Canefri and 

 Preston as belonging to the var. tricolor Kuster are undoubtedly 



1 Hanley and Theobald, Conch. Ind. p. 20, pi. xliv, (ig. 2. The shell figured 

 is apparently a young specimen of L. marginalis. 



2 The second name, Lamellidens Burmanus, on the same page (1170) 

 certainly a lapsus calami for /. tliwaitesi. 



