MUSEUM OF COMPARATIVE ZOOLOGY. 225 
Lima hians Gettin. 
Ostrea hians Gmel. S. N. 3333. 
Lima fragilis Montague, Test. Brit. Suppl., p. 62. 
Lima tenera Turton, Zodél. Journ., V. p. 362, pl. xiii. fig. 2. 
Lima aperta Sowerby, Thes. Conch., I. p. 87, pl. xxii. figs. 26-29. 
One valve was obtained near Santa Cruz, at Station 127, in 38 fms, 
Lima albicoma, n. s. 
Shell small, short, waxen gray, very inequilateral ; sharply truncated above 
and roundly produced below, anteriorly ; hinge-line short, cardinal area trian- 
gular with a narrow long cartilage in a shallow sulcus overhung at the outer 
end by the acutely pointed umbo ; anterior edges of the cardinal and truncated 
areas strongly carinate ; between the carine the truncature is concave with one 
strong and two or three fine radiating threads parallel with and near to the 
longer carina, the rest of this area striate with lines of growth ; the anterior 
angle of the hinge margin hidden in the concavity, when the shell is viewed 
from the side; the posterior angle is visible, but not prominent, though sharp ; 
from this angle to the outer end of the anterior carina the base describes two 
thirds of a circle ; exterior smooth, finely regularly grooved with very numer- 
ous punctate grooves, at the basal margin about ten to the millimeter; these 
grooves radiate primarily from two imaginary lines, one of which (somewhat 
as in L. tenera and L. scabra) is median to the umbo and the base. The 
other is nearly similarly situated with regard to the former, posteriorly, as 
the margin of the truncature is, anteriorly; hinge-line smooth. Max. alt. 
8.00; max. lon. 8.00; max. diam. 4.00; hinge-line 2.75 ; lon. of truncature 
6.00 mm. 
A valve of this interesting species was dredged at Barbados, in 100 fms. ; the 
type was dredged by the Fish Commission steamer “ Albatross” at Station 
2322, near Havana, in 115 fms, 
The peculiarities of sculpture, apart from all the other characters, sufficiently 
separate this from any other described species. 
Genus LIMATULA S&S. Woop. 
Limatula setifera, n. s. 
? Limatula ovata Dall, Bull. M. C. Z., IX. p. 118, 1881 (not of Wood or Jeffreys). 
Shell ovate, inflated, white, with about thirty-four radiating acute ribs, 
strongest in the middle of the valve, with a fine sharp thread in the channel 
between each pair of ribs; both ribs and threads sharp, thin, and produced 
into a series of sharp spines, which in perfect specimens are nearly as high as 
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