The Diatomaceæ of Philadelphia and Vicinity

by Charles S. Boyer

Pl. [24], Fig. 4.

NAVICULA HENNEDYI WM. SM.

Valve elliptical; areas semilanceolate; striæ about 11 in 10 µ, sometimes longer and shorter on the margin; short rows of transverse striæ along the axial area.

Blue clay.

Pl. [25], Fig. 12.

Var. circumsecta Grun.—As in the type but with the lateral areas faintly striate or punctate.

Var. manca A. S.—Valve lanceolate-elliptical, the lateral areas narrow and convergent toward the ends; short rows of transverse striæ along the axial area; striæ, 9 in 10 µ; central pores incrassate.

Blue clay.

Pl. [25], Fig. 11.

NAVICULA LYRA EHR.