934 QUADRULA 
Unio vestitus var. a Heupr, Conch. Fluv. Nank., VIII, 1883, 
pl Lyin, figs E12: 
Quadrula ovata SIMPSON, Syn., 1900, p. 801. 
Acuticosta ovata Haas, Conch. Cab. Unio, 1912, pl. 30, figs. 
8 and Io. 
Parren'sia hunanensis Haas, Nachr. D. Mal. Ges., 1910, p. 97; 
Conch. Cab. Unio, 1912, pl. 30, fig. 9. 
I have never seen this shell, which does not seem from the 
figure to be a variety of Unio westitus as Heude believes. The 
specimen from which it was taken was considerably eroded 
and the species may not group here at all. The teeth as figured 
-are much like those of cornuam-iune. 
Haas, (1. c. 1912), considers his hunanensis a synonym of 
this species. 
QUADRULA CAVEATA (Heude. 
Shell slightly obovate, subrhomboid, convex to subinflated, 
solid, inequilateral; beaks apparently not high nor very full; 
anterior end somewhat narrowed and rounded; dorsal and 
basal outlines lightly curved ; posterior end somewhat obliquely 
truncate above; surface with irregular, strong ridges that fol- 
low the growth lines and often having a few nodules; epider- 
mis chestnut to blackish; pseudocardinals rather small, almost 
parallel with the curved laterals; laterals slightly vertically 
striate, that of the right valve somewhat double; nacre dirty 
whitish. 
Length 89, height 55 mm. 
Length 85, height 50, diam. 30 mm. 
China. 
Unio caveatus HEupE, Conch. Fluv. Nank., III, 1877, pl. xxrv, 
fig. 53. 
Quadrula caveata SIMPSON, Syn., 1900, p. 801. 
Unio contritus Heupr, Conch. Fluv. Nank., VII, 1881, pl. Lv1, 
fig. 103. 
Unio quadrangulosus Hreunr, Conch. Fluv. Nank., VII, 1881, 
pl. ivi, fig. 104. 
I have united under the oldest name three of Heude’s forms, 
which do not seem to me to be separable. The Unio caveatus 
