Fig. 23, Pl. [13], probably a form of prærupta. Newtown Square.
Fig. 28, Pl. [13], from the blue clay.
Fig. 29, Pl. [13], an asymmetrical form, apparently abnormal, but not rare at May's Landing, N. J.
Fig. 17, Pl. [38]. Valve convex on the dorsal side, incised on the ventral; striæ about 15 in 10 µ, closer at the ends; L. 30 µ. Schuylkill River.
Fig. 18, Pl. [38]. Valve arcuate, asymmetrical, broader at one end; terminal nodules large; striæ, 10 in 10 µ; L. 47 µ. Gloucester, N. J., artesian well.
Numerous variations of the above species are illustrated in Schmidt (Atlas, Pls. 285-291).
Actinella Lewis (1865)
(dim. of actin, a ray)
Frustules solitary, or in small clusters, sub-cuneate or nearly linear. Valve arcuate, rounded at one end and suddenly widened at the other into a cup-shaped or lychnoid inflation.
ACTINELLA PUNCTATA LEWIS