As a rule, the median fissures in Pinnularia are turned inwards on the side of the longer edge of the terminal fissures, but not always. In this specimen the median fissures are turned slightly toward the side of the shorter edge of the terminal fissures.
PINNULARIA LEGUMEN EHR.
Valve linear, with more or less triundulate margins and broad, capitate ends; axial area less than one-fourth the width of valve, widened in the middle; striæ strongly divergent in the middle and convergent at the ends, 10 in 10 µ. L. 84 µ.
Fresh water. May's Landing, N. J.
Pl. [30], Fig. 3.
PINNULARIA LEGUMEN VAR. ?
Valve as in type, but with a transverse fascia; striæ, 10 in 10 µ, curved or bent near the ends. L. 84 µ.
This form is not var. florentina Grun.
May's Landing, N. J. (with the type).
Pl. [30], Fig. 4.