The Diatomaceæ of Philadelphia and Vicinity

by Charles S. Boyer

Abundant at Cape May, N. J. Not common elsewhere.

Pl. [14], Figs. 10 and 11.

Gomphoneis CLEVE (1894)

(gomphos, a peg, and neis (naus))

Valve elongated, asymmetrical to the transverse axis; axial area narrow; central area rounded, stigmatic; striæ radiating, costæ alternating with double rows of fine puncta. An indistinct, longitudinal line near the border.

Chromatophores and conjugation have not been determined.

GOMPHONEIS HERCULANEUM (EHR.) CL.

Valve clavate, with rounded apex; costæ, 13 in 10 µ, alternating with double rows of fine puncta, 22 in 10 µ, in oblique rows; axial area narrow, central area rounded, with one stigma.

Gomphonema capitatum Ehr var. herculaneum Ehr., H. L. S., Type Slide No. 177.

Common in the blue clay.