QUADRULA 995 
forms. The distinct radial furrow on the dorsal slope, ending 
in a notch or sinus below and the enormous anal and branchial 
openings of the animal are good characters. 
It has been quite generally believed that the Unio gran- 
iferus of Tea is merely the young, or a small form of this 
species, but it seems to me perfectly distinct. It is a much 
smaller, more inflated, brighter colored form and the nacre is 
usually differently tinted. 
I greatly regret that the well-known name verrucosus of 
Barnes must be changed for the less known tuberculatus of 
Rafinesque. His description of tuberculatus applies to this 
species and cannot be made to cover any other. 
QUADRULA GRANIFERA (Lea). 
Shell suborbicular or subquadrate, inflated, solid, somewhat 
inequilateral; beaks high, full; anterior end and base usually 
rounded ; posterior end truncated, often slightly sinused above 
the posterior ridge; posterior ridge moderately developed ; 
above it there is a light, radial depression ; posterior two-thirds 
of the shell with coarse, scattered tubercles; anterior third 
without tubercles ; epidermis greenish-brown to reddish-brown, 
usually somewhat shining; hinge plate wide; pseudocardinals 
radial, torn; laterals short, straight, that of the right valve 
partly double; beak cavities very deep, compressed; nacre 
purplish, often coppery and shining. 
Length 60, height 60, diam. 35 mm. ~ 
Length 46, height 50, diam. 33 mm. 
Ohio, Cumberland, and ‘lennessee River systems ; northwest 
to Iowa. 
Type locality, Ohio River, Cincinnati, O. 
Unio graniferus Lea, Tr. Am. Phil. Soc., VI, 1838, p. 60, pl. 
xIx, fig. 60; Obs., II, 1838, p. 69, pl. x1x, fig. 60.—HANLEY, 
Biv. Shells, 1843, p. 180, pl.. xxt, fig. 11—CueENu, IIl. 
Conch., 1858, pl. xxv, figs. 3, 3a, 3b—Kuster, Conch. Cab, 
Unio, 1861, p. 212, pl. Lxx, fig. 4.—Rkreve, Conch. Icon., 
XVI, 1864, pl. 1x, fig. 34. 
Margarita (Unio) graniferus Lea, Syn., 1838, p. 15. 
