CLASS PELECYPODA 
15 
Family LEDID2E 
Genus LEDA Schumacher, 1817. 
Shell oblong, rounded in front, produced and pointed behind, margin 
even; pallial line with a small sinus; umbonal area with a linear impres¬ 
sion joining the anterior adductor. (Tryon. S. S. Conch.) 
Type. Area rostrata Linne. 
Distribution. Northern and Arctic seas, Siberia, New England, 
Britain, Mediterranean, Japan, Australia. 
Range in time. Silurian, United States, Europe, South India. 
Leda minuta Fabricius, 1776. 
Plate 5, fig. 5. Plate 19, figs. 2, 2a. 
Fauna Gronl. p. 414. Hanley, Mon. Nuculida, pi. 3, figs. 61, 62. 
Testa myis non dissimilis, oblonga, convexo-compressa, laevis trans- 
versim striata; albo flavicans, interne alba-glaba, extremitae altera rotun 
data breviore, altera producta in rostrum attenuatum oblique truncatum, 
sique angulos 2 formans; deque inferiore atque superiore ltidem innates 
currit carina arcuata minus emineus. Nates albae non striatas, acutae, 
conniventes, versus extremitatem productiorum (quam anticam 1C °)’ 
parum flexae; ante has dorsum testae figuram planam, lanceolatam fine 
striis, fibi impressam habet. Cardinis dentes mimeriosi tarn ante quam 
pone natesvitriusque valvulae 10 numeravi conico-acutos alternatim m- 
sertos. Margo exterior, cardini oppositus, oblonge rotundatus mterger- 
valvulae arete clausae. Diam. 4 lin.; long. 2^4 li n * (Fabricius.) 
Shell oblong, pyriform, tumid, beaks at anterior third, slightly ele¬ 
vated, obtuse, inclined inward, anterior dorsal margin sloping so as to 
bring the somewhat acutely rounded point about midway to the base; 
posterior dorsal margin with about the same slope as the front, direct and 
slightly upturned very near the top, which is very small and squarely 
truncate; ventral margin full and well rounded, with a very slight ernar- 
gination, under the tip; dorsal face very broad, with a wide, flattened, or 
somewhat depressed space, destitute of riblets, m front of the beaks, and a 
long lanceolate one defined by a sharp ridge behind. Length, 11; height, 6; 
diameter, 3 mm. (Gould Invert. Mass.) 
Type locality, Greenland. 
Range. Arctic Ocean to San Diego, California. Also Atlantic. 
Leda minuta lomaensis Dali, 1919. 
Proc. Biol. Soc. Wash., 32:249. 
This form is closely related to L. minuta Fabricius, but differs from 
that species by the following characters: the shell is thinner and more 
