952 NODULARIA 
valve with two pseudocardinals, the upper small, and a single 
lateral; dorsal cavities shallow with a number of pits; muscle 
scars well impressed, the hinder ones long; nacre brilliant 
silvery, iridescent. 
Tength 92, height 22, diam. 13 mm. 
China. 
Unio grayanus Lea, Tr. Am. Phil. Soc., V, 1834, p. 66, pl. rx, 
fig. 26; Obs., 1, 1834, p. 178; pl. 1x, tie. 26.— Reeve, Conch, 
syst., I, 1841, p. 118, pl. L.xxxvin, fig. 4—Hanzey, Biv. 
Shells, 1843, p. 177, pl. xxiv, fig. 5.—Kuster, Conch. Cab. 
Unio, 1856, p. 167, pl. xiv, fig. 5 —CHEnu, Man., 1859, 
II, p. 142, fig. 700—ReEEve, Conch. Icon., XVI, 1865, pl. 
xxv, fig. 191.—Hxrupe, Conch. Fluv., Nank., II, 1877, pl. 
XVI, fig. 36. 
Margarita (Umo)} grayanus Lea, Syn., 1838, p. 14. 
Margaron (Unio) grayanus Lea, Syn., 1852, p. 21 ; 1870, p. 32. 
Unio grayu GrirFity, Grif. Cuv., XII, 1834, pl. xx1, fig. 3. 
Nodularia grayana Simpson, Syn., 1900, p. 806. 
Lanceolaria grayana Haas, Con. Cab. Unio, 1910, p. 44, pl. 2, 
figs. 1-5. 
Unio (Nodularia) gracillimus Roti, Nachr. Deutsch. Mal. 
Ges., 1904, p. 26, pl. tv, figs. b, ec. 
The posterior end is sometimes turned a little to the right 
or left, and the laterals show occasional traces of vertical stri- 
ation. A most striking species and one that is apparently 
quite abundant, judging from the number of specimens in col- 
lections. 
NODULARTA FRUHSTORFERT (Dautzenberg). 
Shell much elongated, solid, very inequilateral, subinflated, 
slightly arcuate; posterior ridge well developed, somewhat 
rounded, slightly curved; ending in a point at the median line; 
base line incurved in the middle, very full towards the poste- 
rior end; surface with irregular growth lines, and a few, heavy, 
irregular, nearly vertical folds on its hinder part, also having 
finer, subradial folds in the umbonal region; epidermis brown- 
ish; pseudocardinals strong, somewhat split up into radial den- 
‘icles ; laterals long and slightly curved; muscle scars well im- 
