NO. 1205. SYXOPSIS OF THE XAIADES SIMPSON. 857 



LAMELLIDENS SCUTUM Sowerby. 



* Unio scutum SOWEKBY, Conch. Icon., XVI, 1868, pi. xciv, fig. 510.'* HAXLEY 



and THEOBALD, Conch. Intl., 1876, p. 22, pi. XLVI, fig. 1. * PASTEL, Conch- 

 Sain., Ill, 1890, p. 167. 



Tenasserim. 



| LAMELLIDENS CORRIANUS Lea. 



* Unio corrianus LEA, Tr. Am. Phil. Soc., VI, 1834, p. 65, pi. ix, fig. 25; * Obs., I, 



1834, p. 177, pi. ix, fig. 25.* HANLEY, Test, Moll., 1842, p. 207; * Biv. Shells, 

 1843, p. 207, pi. xx, fig. 60. * CATLOW and REEVE, Conch. Norn., 1845, p. 

 57. *H. and A. ADAMS, Gen. Rec. Moll., II, 1857, p. 491. * P/ETEL, Conch. 

 Sam., Ill, 1890, p. 149. 



* Margarita (Unio) corrianus LEA, Syn., 1836, p. 38; 1838, p. 25. 



* Marf/aron ( Unio) corrianns LEA, Syii., 1852, p. 38; 1870, p. 61. 



India; Burma; Pegu. 



t LAMELLIDENS GENEROSUS Gould. 



* Unio flenerosiis GOULD, Pr. Bost. S. N. Hist,, II, 1847, p. 220; * Otia Conch., 



1862, p. 210.* HANLEY and THEOBALD, Conch. Ind., 1876, p. 22, pi. XLVI, 

 fig. 4.* P.ETEL, Conch. Sam., Ill, 1890, p. 153. 



* ILaryaron ( Unio) (jenerosus LEA, Syn., 1870, p. 29. 



*?Unw JameUatus SOWERBY, Conch. Icon., XVI, 1868, pi. xciv, fig. 511. 



Burma; Pegu. 



t LAMELLIDENS CANEFRIANUS Simpson. 



* Unio prolenxus TAPPEKONE-CANEFRI,- Am. Mns. Civ. Gen., VII, 1889, p. 349. 

 Prome, Lower Burma. 



tLAMELLIDENS JENKINSIANUS Benson. 1 



*Unio jenkhixoniantts BENSON, Ann. and Mag., X, 1862, p. 185. * HANLEY and 

 THEOBALD, Conch. Ind., 1876, p. 19, pi. XLI, fig. 4. * P.F.TEL, Conch. Sam., Ill, 

 1890, p. 155, 



Assam. 



Subgenus SPATHOPSIS, Simpson. 1900. 

 (Type, Anodonta f/uillaini Reclnz.) 



Shell long, elliptical, compressed, beaks rather low, said to bear con- 

 centrically roughened ridges, with slight plications in front aud behind 

 them; posterior ridge not developed; surface shining, smooth; hinge 

 line narrow, with faint, greatly elongated pseudocardinals and laterals; 



1 Credited hy Sowerby to Benson. 



2 Preoccupied by Lea in 1865 for a North Carolina Unio, hence the name is changed 

 as above. 



; This is figured by Hanley and Theobald as a heavy shell, shaped much like an old 

 Unio buckleyi, and quite different from the other species of the genus. But there 

 is in the U. S. National Museum collection a specimen which is much thinner than 

 the figured shell, and more nearly approaching maryinalis in form. 



