Valve convex on the dorsal, concave on the ventral side; costæ, 3-4 in 10 µ, slightly radiating; apices recurved, capitate.
Blue clay.
Pl. [31], Fig. 18.
EPITHEMIA GIBBERULA VAR. PRODUCTA GRUN.
Valve narrow, lunate, with produced and arcuate apices; costæ radiate, 3-4 in 10 µ; striæ, 16-18 in 10 µ, punctate. L. 58 µ, usually smaller.
Blue clay.
Pl. [31], Fig. 19.
EPITHEMIA MUSCULUS KUETZ.
Valve short, strongly arcuate on the dorsal, concave on the ventral side; apices slightly produced; costæ radiate, about 5 in 10 µ; striæ, 15 in 10 µ, punctate. L. 20-60 µ.
Shark River, N. J.