NODUL ARIA g7I 
teeth strong, the laterals decidedly curved; nacre brownish 
flesh-colored ; muscle scars distinct. 
Length 40, height 27, diam. 17 mm. 
. Japan. 
Unio brandtu Koper, Abh. Senck. Nat. Ges., XI, 1879, p. 
AOR RTT, fast TS: 
Nodularia brandtui Simpson, Syn., 1900, p. 810 —Haas, Con. 
Cab., Unio, 1910, p. 102, pl. 1x, figs. 9-10. 
This is something like NV. haconensis, judging from Kobelt’s 
description and figures, but appears to be very much more 
solid and a darker shell. A dorsal view shows it to be some- 
what wedge-shaped. 
For this species and N’. parcedentata Haas, (Conch. Cab., 
Unio, 1912, p. 102), has established a new section, /nversidens. 
NopULARIA PARCEDENTATA Haas. 
“Shell irregularly rhomboid, quite thin and inflated. An- 
terior end straight above, thence regularly rounded; ventral 
margin straight or slightly convex. Posterior point not prom- 
inent; posterior margin obliquely rounded; dorsal margin 
nearly straight. Beaks situated anteriorly at 24-100 of the 
total length, prominent in young shells, but in older ones lower 
than the highest point of the dorsal margin, eroded, but in 
young shells sculptured with wavy wrinkles, of which remnants 
are visible on the areola of the adults. Posterior slope high, 
triangular, compressed and, owing to the elevated posterior 
ridge, is: distinctly separated from the rest of the shell, the 
inner as well as the upper areal carinz are also recognizable 
as indistinct lines. The areola is small, compressed. Liga- 
ment long, strong; sinulus nearly obsolete, long, lanceolate; 
sinus short, triangular. From above the outline of the shell 
is sharply pointed in front, rapidly increases in width, reach- 
ing its maximum at about the center of the shell, thence grad- 
ually decreasing to the posterior end. Epidermis shining black, 
covered at both ends with a rust-colored deposit. Hinge very 
variable. Only one cardinal tooth in each valve. That of the 
right valve lies in front of the beak, square and jagged above; 
