992 NODUL,ARIA 
Unio fluctiger Lua, Pr. Ac. N. Sci. Phila., III, 1850, p. 152; 
Ji. Ac. N. Sc1.;Phila., DV 51860; "p. 250,-ple xx xix ne 30, 
Obs., VII, 1860, p. 68, pl. Xxx1x, fig. 130.—Kustrr, Conch. 
Cab. Unio, 1861, p. 237, pl. LxxXx, fig. 1—Sowerrsy, Conch. 
Icon., XVI, 1866, pl. x11, fig. 299. 
Margaron (Unio) fluctiger Liza, Syn., 1870, p. 32. 
Nodularia fluctiger Stmpson, Syn., 1900, p. 814. 
Nodularia fluctigera Haas, Con. Cab., Unio, 1910, p. 107, pl. 
x) fies S. 
In the description of this species Dr. Lea states that it be- 
longs in the Cabinet of Mr. Cuming, and no locality is given. 
Two shells, which are labeled Unio fluctiger, are in his col- 
lection and seem to be genuine. These are said to come from 
the Yuruari River, British Guiana, received from R. P. Stev- 
ens. While this may be true, I am inclined to believe that 
there is some mistake about the locality, and that these shells 
came from Southeast Asia. The species is sculptured through- 
out with oblique, subradial ridges and in Lea’s shells this sculp- 
ture is most decidedly zigzag. ‘This is a character not found 
in any South American species, so far as I know, but it is 
very common in the shells of the Oriental region. 
NODULARIA SCOBINATA (Lea). 
Shell small, somewhat elongated, convex inequilateral, sub- 
solid ; beaks only moderately full and high, their sculpture con- 
sisting of strong, zigzag-radial ridges, which extend over the 
entire surface; posterior ridge subangular, ending in a point 
on the median line; dorsal outline almost evenly curved; ante- 
rior end rounded; base line a little incurved, but becoming: full 
behind, then obliquely truncated to the posterior point; in front 
of the posterior ridge there is a wide, radial inflation and in 
front of this a median depression; epidermis greenish, the 
ridges upon it bright green; pseudocardinals subcompressed ; 
laterals curved; anterior scars impressed ; nacre silvery, irides- 
cent. 
Length 34, height 15, diam. 11 mm. 
Siam ; Cochin-China ; Cambodia. 
