QUADRULA 835 
Mississippi drainage area except its southern portion, ex- 
tending to the Tennessee and Arkansas rivers. 
Type locality, Kentucky River. 
Obliquaria (Quadrula) metanevra RAFINESQUE, Ann. Gen. 
oci., Brux., V, 1820, p. 305, pl. LXxXI, figs. 15, 16—CHENU, 
Bibs Conch. tseser., [Ll 1845) -p. 18; pl. 11, fig. 15; 16. 
Unio (ITheliderma) metanevra SwAINson, Treat. on Mal., 
1840, p. 268, figs. 50, 540. 
Quadrula metanevra SIMPSON, Syn., 1900, p. 774.—ORTMANN, 
Ann. Car. Mus., VIII, 1912, p. 255, figs. 6-6a. 
Unio metanever HAN Ey, Biv. Shells, 1843, p. 179, pl. xx1, 
fig. 31.—Rereve, Conch. Icon., XVI, 1864, pl. vir, fig. 25. 
Margarita (Unio) metanever Lia, Syn., 1836, p. 15; 1838, p. 
15. 
Unis metanevrus CONRAD, Monog., I, 1835, p. 10, pl. v, fig. 2. 
=Car, It Acad. N. Sci. St. Lots, VII, 1895, p. 28, pl. x. 
Margaron (Umo) metanevrus Lea, Syn., 1852, p. 22; 1870, p. 
Unie metaneurus Kuster, Conch. Cab. Unio, 1852, p. 50, pl. x, 
fig. 4. 
? Unio nodosus Barnes, Am. Jl. Sci., VI, 1823, p. 124, pl. v1, 
figs. 7, 7a, 7).—CuENu, Manual, 1859, II, p. 138, fig. 663. 
Mya nodosa Katon, Zool. Text-Book, 1826, p. 216. 
A solid, rhomboid form usually covered with tear-like tu- 
bercles and having stronger knobs on the rounded posterior 
ridge. ‘The smaller forms run suspiciously close to Q. tuber- 
osa. 
Var. wardu (Lea). 
Shell more compressed, more delicate and less solid than the 
type, usually smoother, sometimes scarcely tuberculate. 
Ohio ; west to Iowa. 
Type locality, Walhonding River, Ohio; Wassepinicon Riv- 
er, lowa; Coal River, Logan Co., Va. 
Unio wardi Lea, Pr. Ac. N. Sci. Phila., V, 1861, p.-392; Jl. 
mc Ns sci. Phila. 2-12. p s7,.pl. xxiv, fig. 257; Obs., 
IX, 1863, p. 9, pl. xxiv, fig. 257——SowerpBy, Conch. Icon., 
XVI, 1868, pl. txxxt1, fig. 434. 
Margaron (Unio) wardiit Lea, Syn., 1870, p. 33. 
