LAMEr.I.IDF.NS I 171 



laterals remote ; muscle scars rounded and shallow ; nacre 

 salmon-tinted, iridescent. 



Length 70, height 39, diam. 22 mm. 



Ceylon. 

 Unio tlnvaitesii Lka, Pr. Ac. N. Sci. Phila., Ill, 1859, p. 152; 



Jl. Ac. N. Sci. Phila., IV, i860, p. 246, pi. xxxvii, fig. 125 ; 



bbs., VII, i860, p. 64, pi. XXXVII, fig. 125.— Reeve, Conch. 



Icon., XVI, 1865, pi. XXIII, fig. 105. 

 Margaron (Unio) thzvaitesii Lea, Syn., 1870, p. 41. 

 Laniellidens thzvaitesii Simpson, Syn., 1900, p. 856. 

 Lamellidcns marginalis var. thzcaitesi Preston, Rec. Ind. 



Mus. VII, 1912, p. 303. 

 Unio consobrinus HanlEy and Theobald, Conch. Ind., 1876, 



p. 19, pi. XLi, fig. 7. 



Very close to consobrinus and it is quite probable that the 

 two run together. It seems to be rather less solid than that 

 species, is more conspicuously banded, more brilliant, and has 

 a salmon-tinted nacre. 



Lamellidens consobrinus (Lea). 



Shell irregularly long elliptical or subrhomboid, rather solid, 

 inequilateral ; beaks somewhat full and elevated ; posterior 

 ridge high, narrowly rounded, ending in a blunt point below the 

 median line ; anterior end rounded below, angled above ; dorsal 

 slope obliquely subtruncate; surface nearly smooth, covered 

 with a dull chestnut epidermis having a faint, broad, greenish 

 border ; teeth strong, compressed ; laterals remote ; muscle 

 scars impressed ; nacre bluish-white, tinted tlesh-color in the 

 cavities. 



Length 60, height 33. diam. 21 mm. 



Length 65, height 38, diam. 25 mm. 



China ; India ; Ceylon. 

 Unio consobrinus Lea, Pr. Ac. N. Sci. Phila., Ill, 1859, p. 331 ; 



Jl. Ac. N. Sci. Phila., i860, p. 272, pi. xev, fig. 152; Obs.. 



VII, i860, p. 90, pi. XLV, fig. 152. 

 Margaron (Unio) consobrinus Lka, Syn., 1870. p. 46. 

 Lamellidcns marginalis var. consobrinus Preston, Rec. Ind. 



Mus., VII, 1912, p. 304. 



