974 NODULARIA 
their sculpture, in young shells, consisting of concentric, wavy 
wrinkles, which become zigzag-shaped posteriorly and are 
continued over the posterior ridge in curved, parallel lines 
over the dorsal area. . Area low, somewhat compressed, with 
indistinct areal-lines. Areola very small, compressed. Ljiga- 
ment long and strong. Sinulus broad, lance-shaped. Sinus 
short, triangular. Epidermis black with a light silky gloss. 
Dorsal outline lance-shaped, quite blunt in front, abruptly 
increasing in width, the maximum being at one-fourth of the 
length of the shell; thence gradually decreasing to the sharp 
posterior end. Hinge with one cardinal and one lateral in 
the right, two cardinals and two laterals in the left valve. 
Cardinal tooth of the right valve blunt, strong, very jagged, 
in front of it a smaller, weaker, lamelliform auxiliary tooth; 
anterior cardinal of the left valve small, low, posterior elongat- 
ed, high jagged. Interval short, broad. Laterals long, strong, 
in the left valve the lower is the stronger. Angle of the car- 
dinal teeth 15° ; of the laterals 10°. Anterior muscular impres- 
sions deep, that of the adductors united with that of the upper 
retractors; posterior faint; dorsal lying in a row under the 
interval. Mantle-pad in front quite strong, becoming’ flat- 
tened posteriorly. Nacre reddish, bluish posteriorly. 
Length 79, height 46, diam. 30 mm.” (Haas). 
Type locality, Yamashiro, Japan. 
Nodularia hirasei Haas, Nachr. Deutsch. Mal. Ges., 1911, p. 
45; Con. Cab., Unio, 1910, p: 96, pl. xiia, figs. 1-2. 
Group of Nodularia reiniana. 
Shell elliptical oval, very solid, truncated in front and some- 
what biangulate behind, slightly produced at the posterior 
base ; beak sculpture not known; pseudocardinals heavy, elon- 
gated, parallel with the dorsal line. Animal unknown. 
NoDULARIA REINIANA (Kobelt). 
Shell irregularly long ovate, solid, convex, very inequilat- 
eral; beaks nearly terminal and apparently full; posterior 
ridge widely rounded; anterior end of the shell somewhat 
