PARKHVSLA III9 



fig. 1649. This appears to be a young shell with well-pre- 

 served beaks, which have strong, zigzag-radial sculpture and 

 a yellowish-green epidermis. There is a shell in the Lea Col- 

 lection from the Vellaur River in the Coromandel region, of 

 India, which is evidently adult and seems to me to be this. 

 The beaks are so eroded that no sculpture is visible and the 

 epidermis is brown, the posterior basal part is slightly pro- 

 duced, but the pseudocardinals are characteristic of Parrcysia 

 and I have no doubt that it is Gmelin's shell. 



Pakrkysia corp.is (Hanley). 



Shell somewhat obovate, subinflated, moderately solid, in- 

 equilateral ; beaks full and high, with zigzag-radial sculpture ; 

 posterior ridge rounded ; anterior end narrowed and rounded ; 

 base line arcuate, fullest behind the middle ; dorsal outline 

 curved ; outline of dorsal slope rounded, the posterior end be- 

 ing bluntly pointed a little below the median line ; surface 

 nearly smooth, having only faint, concentric sculpture ; epider- 

 mis greenish or brownish-green, shaded with yellowish, in 

 some specimens having indications of rays ; pseudocardinals 

 ragged ; laterals curved, remote ; beak cavities well impressed ; 

 anterior scars deep ; nacre rather dull, whitish, yellowish or 

 pale, lurid purplish, thinner behind. 



Length 44, height 29, diam. 20 mm. 



Length 38, height 25, diam. 16 mm. 



Assam. 

 Unio corbis ILxnley, Biv. Shells, 1856, p. 386, pi. xxiii, fig. 



43.— Hant.fa' and Theobald, Conch. Ind., 1876, p. 22, pi. 



xiA^ fig. 10. 

 Margaron (Unio) corbis Lka, Syn., 1870, p. 50. 

 Parreysia corbis Simpson, Syn., 1900, p. 845. 



Three shells are before me, belonging to the National Mu- 

 seum collection from Assam, India, which agree fairly well 

 with Hanley's description and figure and with the figure in the 

 Conchologia Tndica. I am not certain that the species belongs 

 to the same group with P. nigosa. though they are probablr 

 rather nearlv related. 



