MIOCENE MOLLUSCA AND CRUSTACEA. 71 
Genus ARTENA Conrad. 
Am. Jour. Conch., vol. 6, 1870, p. 76. 
“Triangular, thick; surface with acute, concentric, prominent ribs; hinge 
with three cardinal teeth in the right valve, two of them diverging, distant, 
the anterior one under the apex, robust, direct, curved; left valve with three 
diverging distant teeth; lateral tooth very small, pyramidal; pallial sinus 
very small and angular. 
“Cytherea staminea Conrad, Miocene Foss., Pl. xx1, fig. 1. 
“This genus is readily distinguished from the other genera of the 
family by one thick anterior tooth in the right valve instead of two approx- 
imate teeth as in Meretrix, Caryatis, ete., and by two distant, thick, nearly 
equal teeth of the opposite valve, and also by the very small pallial sinus, 
the exterior ribs, ete.” 
The above is Conrad’s description of this genus given in the Am. Jour. 
Conch., 1871, being copied literally by Tryon in his Systematic and Strue- 
tural Conchology, where he gives the orthography of the name Artenia 
and dates it 1870. A specimen of A. staminea which is probably from 
South Carolina, and is fully grown and much thickened, shows the teeth 
well developed. Those of the right valve are as Mr. Conrad describes 
them, except perhaps that the one opposite or beneath the beak is not 
“curved.” It is “direct;” but it would be difficult to interpret it as curved 
in any sense. The anterior tooth in the right valve is small and the pos- 
terior one large, while in the left valve the reverse is the case. As to the 
merits of the genus, it appears to me that all the features of it are fully 
embraced in those of Anaitis of Roemer, as shown in Venus plicata Gmelin, 
and that the separation was not necessary 
v 
Furthermore, the typical 
species, A. staminea Conrad, is much more nearly allied to Venus than to 
Cytherea, under which it is placed by Tryon. 
