PARIIEYSIA. 171 



rotundato-ovalis, oninino prseter ad extremitatein auticam sub- 

 radiatiin granoso-plicitera. 



The dimensions of three specimens given at the foot of the 

 original description are as follows : — 



1. 2. 3 (young shell). 



Lono- 52 45 'M mm. 



Lat 35 32 26-5 mm. 



Diam 22 20 17 mm. 



Length of ligament 23 20'5 16 mm. 



Jfah. Irawady River at Eliamo. 

 The type is in the Indian Museum. 



305. Parreysia (Parreysia) sikkimensis (Lea). 



Parreysia {Pdrreysia) siklcimeasis (Lea); Simpson, Washington, 

 D.U., Smiths, lust., Nat. Mas. Proc. xxii, 1900, p. 845. 



Unio sikkimensis, Lea, Proc. Acad. Nat. Sci. Philadelphia, iii, 

 1859, p. 151 ; Journ. Acad. Nat. Sci. Philadelphia, iv, 1859, 

 p. 251, pi. 39, fig. 131 ; Obs. Genus Unio, vii, 1860, p. 09, pi. 39, 

 fig. 131 ; Sowerbv, Conch. Icon, xvi, 1868, pi. 76, hg. 400 ; 

 11. & T., C. I. 1870, p. 6, pi. 11, fig. 4, and p. 44, pi. 107, 

 figs. 0, 7 ; Pajtel, Couch. Sara, in, 1890, p. 167. 



Mart/aron (Unio) aikkunensis, Lea, Syn. 1870, p. 64. 



Orujinal description : — Testa lajvi, obovata, insequilaterali, sub- 

 infiata, postice obtuse biangulata ; valvulis crassiusculis ; natibus 

 prominidis; epidermide luteo-fusca,eradiata ; dentibuscardinalibus 

 parvulis, brevibus crenulatis, in utroque valvule duplicibus ; later- 

 alibus brevibus subciirvisque ; margarita alba et iridesceute. 



JIab. Sikkim {JI. Cuinin<j Sf Prof. Hanley). Represented in the 

 Indinn Museum by specimens from Sibsagar, Assam (*S. E. Peal)\ 

 Siliguri ; Xamtsik ; Uihang, and Cachar. 



Xo dimensions being given with the original description, those 

 of three specimens in the Indian Museum are a])pended : — 



1. 2. 3. 



Long 28-5 28-25 19-5 mm. 



Lat.'' 38-5 37-25 27-25 mm. 



Diam 20 19-25 12-25 mm. 



The species though varying somewhat, usually in the posterior 

 region, is easily distinguishable from others of the group by its 

 considerable convexity in proportion to its size and by its short, 

 broad, and generally ovately rounded form. 



300, Parreysia (Parreysia) gowhattensis {Theobald). 



Parreysia (Parrei/sia) f/owhattensis (Theobald) ; Simpson, Wash- 

 ington, D.C., Smiths. Inst., Nat. Mus. Proc. xxii, 1900, p. 845. 



Unio gowhattensis, Theobald, J. A. S. B. xlii, 1873, p. 208, pi. 17, 

 tig. 4; Poetel, Conch. Sam. iii, 1890, p. 154. 



Original description : — Testa quadrato-ovata, antice rotundata, 



