1072 SIMPSONRLLA 



fAnodonta heldii Kuster, Conch. Cab. Ano., 1873, p. 64, pi. 



XIX, fig. I. 

 Anodonta chincnsis Kuster? Where? 



This seems to be an abundant form and quite a variable 

 one. I have no doubt but that Lea's Unio hengalensis is the 

 same as the Anodonta purpurea of Valenciennes, as is Lea's 

 Unio mauritianus and that the localities, India and Mauritius, 

 given by him are wrong. The shell is usually somewhat long 

 rhomboid, the anterior end being a little narrowed, the dorsal 

 and ventral outlines being nearly parallel. Sometimes, how- 

 ever, the outline is almost evenly elliptical or slightly obo- 

 vate. Specimens of Anodonta purpurea, so labeled by More- 

 let, and from his collection, belong to the National Museum 

 and do not in any essential character differ from Lea's types 

 of U. hengalensis and mauritianus. Sometimes the texture of 

 the shell is coppery-tinted with green, and in other cases it is 

 decidedly violet. 



SiMPSONELI.A CREPlvRA (Lea). 



Shell somcAvhat elongated, almost regtilarly obovate, rather 

 thin, convex, inequilateral ; beaks not full or high, their sculp- 

 ture zigzag-radial ; posterior ridge low, rounded, sometimes 

 feebly double and at such time ending in a very slight bian- 

 gulation behind ; surface with irregular growth lines ; epi- 

 dermis dull brownish, banded with greenish and feebly rayed, 

 subshining ; teeth reduced to mere lineal vestiges ; muscle scars 

 shallow ; nacre dull, lurid, coppery-tinted, a little thickened in 

 front, slightly iridescent behind; prismatic layer wide, dull, 

 copper\'-tinted. 



I,ength 85, height 43, diam. 27 mm. 



Luzon Island, Philippines. 

 Anodonta crepera Lea, Pr. Zool. Soc. Lond., 1850, p. 198; Jl. 



Ac. N. Sci. Phila., IV, i860, p. 238, pi. xxxiv, fig. 117; 



Obs., VII, i860, p. 56, pi. XXXIV, fig. 117. — Ci^ESSiN, Conch. 



Cab. A.no., 1873, p. 97, pi. xxix, figs. 5, 6. 

 TAnodon creperits Sowerby, Conch. Icon., XVII, pi. vni. fig. 



16. 



