846 QUADRULA 
Type locality, Colorado River, La Grange and Leon Co., 
dexas: 
Unio speciosus Lea, Pr. Ac. N. Sci. Phila., VI, 1862, p. 168; 
jl. Ac. N. Sex Phila, V,) 1622p: 207, ipl sxe, ic pees 
Obs., IX, 1863, p. 29, pl. xxx1, fig. 276.—SoweErsBy, Conch. 
Icon., XVI, 1868, pl. LXxxIv, fig. 447. 
Margaron (Unio) speciosus Lea, Syn., 1870, p. 33. 
Quadrula speciosa SIMPSON, Syn., 1900, p. 778. 
Lea has four shells in his collection labeled Unio speciosus. 
I have given above the measurements of the largest one 
and am doubtful whether any of them are adult. ‘They are 
very much like young forsheyi, but are more compressed and 
elongated. 
QUADRULA APICULATA (Say). 
Shell subrhomboid, rather short, slightly inequilateral, sub- 
solid to solid; beaks high, moderately full; posterior ridge well 
developed, narrowly rounded, angled or showing a tendency 
to be double, ending in a point or feeble biangulation at the 
base of the shell; in front of and behind it there are radial 
depressions ; anterior end rounded, sometimes obliquely trun- 
cated above; basal line sinused in front of the posterior ridge; 
outline of dorsal slope raised to an angle behind the ligament, 
squarely or obliquely truncate below; surface covered with 
fine, close pustules, which are often laid down in zigzag pat- 
terns; epidermis greenish in young shells, ashy-brown in old 
ones, dull; pseudocardinals radial, somewhat split; lateral of 
right valve partly double; beak cavities moderately deep; an- 
terior scars well impressed: nacre white, iridescent behind. 
Length 72, height 59, diam. 37 mm. 
Length 60, height 52, diam. 32 mm. 
Louisiana to Texas. 
Type locality, New Orleans, La. 
Unio apiculatus Sav, New Harm. Diss., II, No. 2, 1829, p. 309 ; 
Am. Conch., VI, 1834, pl. L11—Conrap, Monog., IX, 1837, 
p. 78, pl. xi1v, fig. 1—Hantey, Biv. Shells, 1843, p. 178, pl. 
Xxill, fig. 51.—CHenu, Manual, 1850, II, p. 142, fig. 696.— 
Reeve, Conch. Icon., XVI, 1864, pl. 1, fig. 11. 
