NAVICULA MACULATA (BAIL.) CL.
Valve lanceolate-elliptical, with produced or sub-rostrate ends; axial area narrow, wider near the ends and dilated to a rounded, transverse central area; striæ radiate, 6 in 10 µ, puncta, 7 in 10 µ, in irregular, longitudinal rows. L. 90 to 120 µ (Cl.).
Stauroneis maculata Bail.
Navicula fischeri A. S.
Blue clay. Along the coast, especially southward.
Pl. [24], Fig. 1.
NAVICULA LATISSIMA GREG.
Valve oblong-elliptical or elliptical-lanceolate, with sub-cuneate ends; axial area lanceolate, widened in the middle to an orbicular space; striæ radiate, 7 in 10 µ, puncta, 11 in 10 µ, the median striæ alternating with short striæ along the sides. L. 50-150 µ (Cl).
Blue clay. Pavonia, N. J., artesian well.
Pl. [24], Fig. 3.