930 QUADRULA 
This species varies much in outline, occasionally being much 
narrowed in front, while often shells are quite high anteriorly. 
Some specimens are rather short and others are considerably 
lengthened, the latter establishing a connection with Heude’s 
Unio lelect. 
Var. lelect (Heude). 
Shell considerably elongated. 
Length 72, height 45 mm. 
J,ength of an author’s specimen 80, height 45, diam. 29 mm. 
Unto lelecit Heupr, Conch. Fluv. Nank., I, 1875, pl.-tv, fig. 12; 
pl. v, fig. 14. 
Unio leat var. lelecs Paste, Conch. Sam., III, 1890, p. 157. 
Quadrula lea var. leleci SimMpson, Syn., 1900, p. 8oI. 
Unio richthofeni von Martens, S. B. Nat. Fr., 1875, p. 3; 
Nov. Conch, 1V7-1876, p2156, pl. Cxxxvip digs: 1-3. 
The figure of Unio leleci in the Conchyliologie Fluviatile 
Nanking does not differ from specimens which Dr. Lea has 
in his collection under the name Unio leat Gray. But an 
author’s specimen of Unio leleci in the National Museum col- 
lection is much elongated, is rather more inflated than typical 
leai and has smaller nodules. 
Var. truncatula ( Neumayr). 
“Shell rather small, low, thick, very inequilateral, somewhat 
elliptical, with a sloping basal margin and a broad, obliquely 
truncate posterior margin. Dorsal margin curved. Beaks not 
very prominent, very little eroded. Surface with strong sculp- 
ture, which is heavier posteriorly. The beaks are surrounded 
with coarse ridges, towards the basal margin are more rather 
irregularly arranged tubercles; posterior slope with coarse. 
subparallel ridges, which become straight towards the posterior 
margin. Hinge of the right valve with a prominent, stout, 
quadrate cardinal tooth ; lateral tooth long, lamelliform, curved. 
Muscular impressions feeble. Nacre white. Color of epider- 
mis. ? 
Length 39.5, height 25, diam. 15 mm.” (Neumayr). 
