MUSEUM OF COMPARATIVE ZOOLOGY. 249 
Suspcenus LEDA ScuumacueEr (s.s.). 
Leda Carpenteri Datt. 
Leda Carpenteri Dall, Bull. M. C. Z., IX. p. 125, 1881. 
Plate VIII. Fig. 11; Plate IX. Fig. 3. 
Habitat. Barbados, 100 fms. ; Station 5, 229 fms. ; Station 9, 111 fms., bot- 
tom temperature 55°.0 F.; Station 21, 287 fms.; Station 128, 180 fms., off 
Frederikstadt ; off the Carolina coast, U. S. Fish Commission, 1885, 
Since describing this species I have been able to compare it with specimens 
dredged by the Fish Commission in some abundance farther north, and with 
Leda clavata Calcara, a Sicilian fossil which is its nearest relative. LZ. Carpen- 
tert differs from clavata in its greater smoothness and in having the hinge-line 
narrower, the teeth smaller, more delicate, and less numerous, especially the 
anterior series ; the ligamental pit is much smaller, and the series of teeth 
are straighter and with much less margin between them and the edge of the 
dorsal crest. The raised line inside the rostrum is in clavata nearly in the 
middle of the shell; in Carpenteri it is invariably nearer the dorsal edge, thus 
making the dorsal channel distinctly narrower than the ventral one. 
In fresh specimens of L. Carpenteri, especially youngish shells, the pale green 
epidermis is marked by a beautiful radiating series of arched strie, only visi- 
ble with a glass except in very marked cases, or near the ventral edges of the 
valves where the striation is strongest. It is absent in decorticated specimens, 
and so would appear to be purely a character of the epidermis, 
Leda clavata has been erroneously united with L. cuspidata, which differs 
both in shape and sculpture. I have not seen any recent specimens of 
clavata or cuspidata. Some marked as such in the Jeffreys collection were 
L. Carpenteri, 
Leda messanensis Srcuenza. 
Leda messanensis Seguenza, Dall, Bull. M. C. Z., IX. p. 124, 1881. 
Habitat. Station 19, 310 fms. ; Station 20, 220 fms. ; Barbados, 100 fms.; 
Sigsbee, off Havana, 450 fms. 
This species, which I have compared with specimens received from the 
author, varies in sculpture much like the others, being sometimes almost 
wholly smooth, and at others with well developed concentric sculpture; it also 
varies remarkably in proportional length, some specimens being yery short 
and high. In considering these variations, one cannot help surmising that the 
present number of nominal species of these little shells will eventually require 
to be diminished, 
