298 BULLETIN OF THE 
Cardiomya costellata, var. corpulenta Dat. 
Plate Ill. Fig. 9. 
The variety corpulenta Dall is like a giant curta striated all over, and about 
15.0 mm. long. A valve was dredged at Station 5, in 229 fms., and a frag- 
ment at Station 228, near St. Vincent, in 785 fms. It differs from C. striata 
Jeffreys in the shorter and less differentiated rostrum and the alternately larger 
and smaller radii, which are also more distant and sharper, while the concen- 
tric strie are much less evident. Still, in the type these characters intergrade, 
as they might be seen to do here if we had specimens enough to compare. 
Cardiomya striata JErrreys. 
Neera striata Jeffreys, Valorous Moll., Ann. Nat. Hist., Dec. 1876, p. 495; P. Z.S., 
Nov. 1881, p. 944, pl. lxxi. fig. 11, 1882. 
2 Necra alternata D’Orb., var., Dall, Bull. M. C. Z., IX. p. 110, 1881. 
Necra multicostata Verrill and Smith, Trans. Conn. Acad. Sci., V. 559, pl. lviii. 
fig. 40; Proc. U.S. Nat. Mus., III. p. 398, 1880. 
Plate III. Fig. 10. 
Habitat. Station 36, 84 fms.; Station 5, 152 fms.; U. S. Fish Commission, 
off the Carolina coast, Station 2601; off Martha’s Vineyard, Station 1038, etc.; 
off Newport, Rhode Island, Station 874, and others. 
This fine shell differs from some of the varieties of C. costellata only in size. 
It bears the same relation to them that the var. corpulenta does to the var. 
curta. But taken by itself it seems so distinct that I have concluded to leave 
it separate for the present. It should be stated that Dr. Jeffreys’ remark as 
to the radiation not being coarser posteriorly, is correct only for the one or two 
specimens first obtained, and even in them it is only partially exact. The vast 
majority have the sculpture decidedly stronger toward the rostrum. I may 
also add, that none of the specimens in the Jeffreys collection at Washington 
have the rostrum quite as straight as in the figure in the P. Z.S. It is a little 
upturned in all of them, though the particular specimen figured may not have 
had that peculiarity. 
There is every probability of the correctness of Prof. Verrill’s observation: 
“ Perhaps all these forms may eventually prove to be varieties of one species.” 
(Trans. Conn. Acad. Sci., V. p. 560, 1882.) 
Suspcenus LEIOMYA A. Apams. 
Leiomya A. Adams, Ann. Mag. Nat. Hist., 1864, p. 208. 
An anterior prominence or cardinal tooth in each valve, anterior and pos- 
terior laterals in the right valve, left valve without laterals. Cartilage in a 
