QUADRULA 919 
Unio fibrosus Hxupr, Conch. Fluy. Nank., II, 1877, pl. x1, fig. 
22. 
Quadrula fibrosa SIMPSON, Syn., 1900, p. 798. 
Unio spuriuws Heupr, Conch. Fluv. Nank., II, 1877, pl. x1, 
fig. 23. 
I have examined author's specimens of both Unio fibrosus 
and spurius and they so unite the figures given by Heude of 
the two species that I believe they are both one thing. The 
form is more elongated than tientsinensis or sonata, is more 
triangular and the beaks are higher than in either. 
QUADRULA SAT,APUTIUM von Martens. 
“Shell orbicular-subquadrate, heavy, inflated, sculptured 
with elevated warts of varied shape, linear, subcircular or 
‘ forked over the whole surface; epidermis yellowish-brown, not 
shining: rounded before; subtruncate behind; ventral margin 
slightly, posterior margin greatly undulated by larger, heavy, 
elongated, radiating pustules; beaks obtuse, eroded. Three 
cardinal teeth in the right valve, the middle one heavy, trian- 
gular, deeply sulcate, the posterior rather ‘smooth, weak, 
oblique and the anterior sublinear, small; in the left valve two, 
triangular, sulcate, anterior moderately, posterior very heavy ; 
lateral teeth quite short, slightly curved, one in the right valve, 
transversely striate on both sides like a Castalia; in the left 
valve two, parallel. the upper one the smaller, transversely 
striate on the inner face, the lower swollen posteriorly, trans- 
versely striate on the upper face; sinulus none. Nacre yellow- 
ish-white, scarcely pearly ; impressions of the anterior adduc- 
tors very deep; accessory impressions small, oblong. 
Length 38, height 33, diam. 20.5 mm. Beaks in 2-5 of the 
length.” (von Martens). 
Type locality, Thuyen-Quan, Anam. 
Ouadrula salaputium von Martens, Nachtr. Deutsch. Mal. 
Ges., 1902, p. 132. 
“Only a single specimen is before me, so that I can not tell 
how largely individual characters, as for instance, the color 
of the nacre, are included in the above description. It differs 
