Fresh water.
Pl. [27], Fig. 16.
NAVICULA HUMILIS DONK.
Valve elliptical, with broad, rostrate ends; axial area narrow; central area small; striæ radiate and distant in the middle, convergent at the ends, coarse, appearing costate, averaging 9 in 10 µ. L. 19 µ. As Donkin states, the striæ are "very conspicuous."
Navicula hungarica var. capitata (Ehr.) Cl.
Navicula globiceps Lagerstedt, according to Cleve.
Willistown, Pa.
Pl. [27], Fig. 24.
NAVICULA PINNATA PANT. ?
Valve lanceolate, obtuse; axial area narrow, widened in the middle; striæ coarse, 7 in 10 µ in the middle, radiate, 10 in 10 µ at the ends and transverse, indistinctly lineate. L. 40 µ.