QUADRULA 913 
Subgenus LAMPROTULA Simpson, 1900. 
Lamprotula S:MPsSoNn, Syn., 1900, p. 796. 
Shell rounded to triangular, inflated, with high beaks; beak 
sculpture consisting of a few coarse, subparallel ridges, which 
are slightly doubly looped; surface of the shell generally cov- 
ered with coarse nodules or knobs; posterior slope radially 
ridged; epidermis dark; hinge strong; secondary lateral of 
right valve well developed; cavity of the beaks deep and com- 
pressed: nacre mostly whitish, usually radially, granularly 
striated outside the pallial line, and having one or more pecu- 
liar calluses behind and below the laterals, which are iridescent 
and granularly striate. 
Animal unknown. 
Type, Chama plumbea Chemnitz. 
Group of Ouadrula plumbea. 
Shell rounded, slightly angulated behind the ligament, solid, 
moderately inflated, covered with coarse pustules, and having 
broken, upcurved corrugations on the posterior slope; epider- 
mis light brownish; hinge rather strong, somewhat flattened ; 
laterals vertically striated. 
QUADRULA PLUMBEA (Chemnitz). 
Shell suborbicular, solid, somewhat inflated, inequilateral ; 
beaks moderately high, turned forward; surface sculptured 
with oblique corrugations in the umbonal region, which de- 
scend toward the anterior base, having irregular, radial folds 
below and behind; the basal and anterior parts of the shell are 
somewhat tuberculous; epidermis brownish; hinge plate wide 
and flat; pseudocardinals very strong; laterals with strong 
vertical striation; beak cavities no doubt deep; nacre white. 
Length of figure 42. height 45 mm. 
South East Asia, probably. The locality, “South Sea,” given 
by Chemnitz is, no doubt, erroneous. 
Chama plumbea CurmMnitz, Conch. Cab., XI, 1795, p. 237, pl. 
ccul, figs. 1991, 1992.—Woon, Ind. Test. Rev., 1856, p. 52, 
pl. rx. fig. 6. 
Ouadrula plumbea Stmevson, Syn., 1900, p. 797. 
