944 CUNEOPSIS 
The species, which I have placed in Cuneopsis, though vary- 
ing considerably in details are all evidently closely related and 
form a natural group. This group is characterized by having 
elongated, intlated shells with unicolored, silky, brownish ept- 
dermis, two, more or less connected, pseudocardinals in the 
left valve with a deep pit between them, one in the right valve 
with a deep pit behind it, very deep beak cavities, and elongat- 
ed, oblique posterior muscle scars. Owing to our almost 
total ignorance of the anatomy of most of the Oriental Natades 
much of the classification I have offered is only tentative. I 
have endeavored to do the best I could from the shell char- 
acters, but in most cases the beak sculpture is completely 
eroded away, and for some of the species I have only seen 
figures or descriptions, which do not cover some of the most 
important points. 
Key to species of CUNEoPSIS. 
Shell more or less obliquely truncate above posteriorly. 
Strongly curved and twisted. pisciculus. 
Not curved or twisted. rufescens. 
Shell. not obliquely truncated, pointed behind at the median 
line. 
Distinctly swollen in front. ~ capitata. 
Scarcely swollen in front, inequivalve. celtiformis. 
Subtruncate above the posterior ridge, drawn out to a long 
point behind. heudet. 
Truncate anteriorly. tauriformis. 
CUNEOPSIS CAPITATA (Heude). 
Shell wedge-shaped, long triangular, inequilateral, solid, 
rounded and infiated a short distance in front, becoming sud- 
denly contracted behind the inflation; beaks high, full, placed 
close to the anterior end; anterior end rounded ; anterior part of 
the base rounded; behind the anterior inflation there is a sinus; 
outline of dorsal slope nearly straight, the shell ending behind 
in a point; surface with low ridges, which follow the growth 
lines; epidermis brownish, silky; left valve with an anterior, 
