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. Mislopia 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 irom 
Siam, many of which probably extend to Burma. 
Genus ANODONTA, Brugiere. 
No. 1.—Anoponta soLENIFoRMIs, Bens. Assam. 
Benson. J. A. 8. B. V., 750. 
The type specimen is in the Asiatic Society’s Museum (now the 
Imperial Museum). There is also an A. solenzformis, 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 Iycetopus emarginatus, Lea. (Jour. Acad. Nat. Sei. 
Phil. 2nd Ser. V., 398, pl. 50, £. 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. solenzfor- 
mis with the animal living are a peculiar desideratum. 
No. 2.—Anoponta Satwentans, Gould. Salween R., Burma. 
Gould, Proc. Bost. Soc. Nat. Hist. I., 158. 
Ot. Conch, p. 193. 
A very peculiar broad shell, belonging to Monocondylea. (See 
next species.) I have never seen this form. 
No. 3.—Anoponta Inoscunaris, Gould. Salween R., Burma. 
Gould, Proc. Bost. Soc. Nat. Hist. I. 158. 
ns Ot. Conch. p. 193. 
Subsequently in the same volume, p. 161, Dr. Gould 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 Otva Conchologica, Gould, in describing 
the genus, adds in brackets “perhaps equivalent to Monocondylea, 
D’Oxb,” So far as the shell is concerned, this is undoubtedly the 
