The Diatomaceæ of Philadelphia and Vicinity

by Charles S. Boyer

Pl. [12], Fig. 5.

Fig. 6 represents a variety with coarser striæ from the Schuylkill River. Both are easily mistaken for Fragilaria intermedia.

SYNEDRA FULGENS (GREV.) WM. SM.

Frustules geminate or flabellate on a stipe. Valve slightly inflated in the middle and at the apices; pseudoraphe narrow; striæ finely punctate, radiate at the ends.

Marine. Atlantic City.

Pl. [11], Fig. 10.

SYNEDRA AFFINIS KUETZ.

Valve lanceolate; striæ marginal, leaving a broad lanceolate pseudoraphe.

Common along the coast.

Pl. [12], Fig. 3.