Forma minor—Valve rhombic-lanceolate, smaller than the type.
May's Landing, N. J.
Pl. [17], Fig. 13.
ANOMŒONEIS FOLLIS (EHR.) CL.
Valve rhomboid, tumid in the middle and obtuse at the produced ends. Central area lanceolate; striæ radiate in the middle, transverse at the ends.
Navicula follis Ehr.
Navicula trochus Kuetz.
Reported by Lewis as very rare in the blue clay of the Delaware River. I have not seen it in this locality. The figure is drawn from a specimen in the W. Bridgewater, Mass., deposit.
Pl. [17], Fig. 14.