Q22 OUADRULA 
Unio (Quadrula) ledtkei Route, Nachr. Deutsch. Mal. Ges., 
1904, p. 25, pl. 3; pl. 4, fig. a—DautTzenBerc and Fiscuer, 
Ji. -de‘Conch:, Lligareo5) p21. 
Dautzenberg and Fischer, (1. c.), consider this to be only a 
variety of nodulosus Wood. 
QUADRULA BLAISEI Dautzenberg and H. Fischer. 
“Shell oval, elongated, very thick and heavy, greatly inflated 
anteriorly and with two diverging carine, the lower of which 
soon disappears, while the posterior, decreasing in size towards 
the posterior extremity, sharply limits the posterior slope. Sur- 
face ornamented with irregular, concentric folds, which to- 
wards the summits become more pronounced and are mingled 
with irregular tubercles, becoming obsolete, however, poste- 
riorly where the shell is compressed and almost smooth. Pos- 
terior slope with strong, oblique folds, which undulate the 
dorsal margin. Ligament corneus, strong, but slightly prom- 
inent. Cardinal plate large and overhanging a deep cavity. 
Hinge very thick, in the right valve a single, large, sulcate 
cardinal tooth (situated between a deep cardinal pit and the 
equally deep impression of the anterior adductor muscle) and 
an elongated lateral; in the left valve, two cardinal teeth (the 
anterior small, situated between a deep cardinal pit and the 
equally deep impression of the anterior adductor, the posterior 
strong, sulcate) and two elongated, lamellar laterals. Impres- 
sion well marked. Epidermis fibrous, deep olive. Nacre 
white, iridescent. 
Length 08, height 62, diam. 55 mm.” (D. and F.). 
Tvpe locality, Bas Luc-Nam, village of Van-len, Tonkin. 
Unio (OQuadrula) blaisei Dau'zeNnerRG and FiscuHer, Jl. de 
Conch: LUI, 10905, p2i0./plo way figs ae 2: 
“This species is distinguished from U. leat Gray by its 
heavier shell, much more inflated in the umbonal region and 
by the two, elevated carinz that diverge from the beaks. It 
is also related to Ouadrula liedtkei Rolle (Nachtrichtsbl. d. d. 
Malak. Ges. 1904, p. 25, pl. 3 and pl. 4, fig. a, a) but this latter 
species is more regularly oval, does not have the characteristic 
carine of blaisei and appears to us to be only a variety of U. 
nodulosus Wood.” 
