660 UNIO 
Unio quadrilaterus Lea, Pr. Ac. N. Sci. Phila., VII, 1863, p. 
192; Jl. Ac: N.cSeis Phila:, Vib 866) p35, {ple phe ee Oss, 
XT, 1867, p9; ply figede 
Margaron (Unio) quadrilaterus Lea, Syn., 1870, p. 51. 
Unio complanatus var. quadrilaterus Simpson, Syn., 1900, p. 
72s. ; 
Variable in color of nacre and degree of inflation. 
UNIO ROSTRUM Lea. 
Shell elongated, rhomboid, convex, subsolid, generally full- 
est at the posterior ridge; dorsal and basal lines parallel, the 
latter incurved ; beaks scarcely infiated or elevated, their sculp- 
ture not seen, posterior ridge high, single and angular above, 
showing a tendency to become double below, ending at or 
very near the base line in a blunt point or biangulation; sur- 
face with strong, uneven growth lines; epidermis tawny, 
tawny-brown or greenish-brown, sometimes feebly raved, 
rather smooth and shining; pseudocardinals rough, double in 
each valve, the upper in the right valve small; laterals remote, 
straight; beak cavities shallow; muscle scars large and im- 
pressed ; nacre whitish or flesh-colored. 
Length 98, height 44, diam. 26 mm. 
North Carolina. 
Type locality, Catawba River, Gaston Co., N. C. 
Unto wheatley:. Les, Pr. Ac. N. Sei. Phila, ie57,0.- pase lle 
Ac. Ne-Sci. Phila:, V, 1861, p.054, -pl..1, ss 2oo hse ane 
Ps 5, pl.a, Nee 200. 
Margaron (Umeo) catawhbensis LEA, Syn., 1870, p. 52. 
Unio catawbensis SIMPSON, Syn., 1900, p. 725. 
Unio rostrum Lea, Pr. Ac. N. Sci. Phila., VIII, 1861, p. 391; 
Jl. Ac. Nv Sci. Phila. V, 1862, p. 201, pl. xxix, fig. 270; 
Obs.; 1X) 1863s p23, plicexix) fia 27a, 
Margaron (Unio) rostrum LEA, Syn., 1870, p. 52. 
Unio oblongus Lea, Pr. Ac. N. Sci, Phila., Il, 1872, p. 158; 
ji. Ac. N. Set? Phila., V1) 1874, p.052) plesvain nebo 
Obs., XIII 1874, p: 56, pl. xvi, ficiese: 
. 
