150 Contributions to Indian Malacology. [No. 2, 



form, almost subquadrate. The posterior portions of the valves were 

 often covered by the remarkable fresh water Bryozoon Hislopia of 

 Carter, apparently a new species. 



I have other species from Pegu, but I am unable at present to com- 

 pare them with the numerous named forms described by Lea from 

 Siam, many of which probably extend to Burma. 



Genus ANODONTA, Brugiere. 

 No. 1. — Anodonta soleniformis, Bens. Assam. 

 Benson. J. A. S. B. V., 750. 



The type specimen is in the Asiatic Society's Museum (now the 

 Imperial Museum). There is also an A. soleniformis, D'Orbigny, but 

 Mr. Benson's name is the oldest, as it was published in 1836. 



Mr. Lea has described a species from Siam, evidently very closely 

 allied to this, as Mycetopus emarginatus, Lea. (Jour. Acad. Nat. Sci. 

 Phil. 2nd Ser. V., 398, pi. 50, f. 305). As the animal has not been 

 observed, it may be doubtful if it is really a Mycetopus. At the same 

 time the character of both the Siam and Assam shells are so distinct 

 from those of any true Anodonta, that perhaps the best provisional 

 classification is that adopted by Mr. Lea. Specimens of A . solenifor- 

 mis with the animal living are a peculiar desideratum. 



No. 2. — Anodonta Salweniana, G-ould. Salween R., Burma. 



Gould, Proc. Bost. Soc. Nat. Hist. I., 158. 

 Ot. Conch, p. 193. 



A very peculiar broad shell, belonging to Monocondylfsa. (See 

 next species.) I have never seen this form. 



No. 3. — Anodonta inoscularis, G-ould. Salween B., Burma. 



Gould, Proc. Bost. Soc. Nat. Hist. I. 158. 

 Ot. Conch, p. 193. 



Subsequently in the same volume, p. 161, Dr. G-ould suggested 

 that this species might be the type of a new genus which he named 

 Pseudodon. This name is by Adams quoted as a synonym of Anodonta, 

 but the type species is not quoted under that genus, nor, so far as I can 

 detect, under any other. In Otia Conchologica, Gould, in describing 

 the genus, adds in brackets " perhaps equivalent to Monocondyloea, 

 D'Orb." So far as the shell is concerned, this is undoubtedly the 



