Epithemioideæ
NITZSCHIA EPITHEMIOIDES GRUN.
Valve linear, with cuneate, rostrate apices; slightly constricted on the keel side; keel puncta, 8 or 9 in 10 µ, extending as costæ across the valve; striæ delicate, 22 in 10 µ. L. 47 µ.
Brackish water, Long Island Sound.
Pl. [32], Fig. 21.
Grunowia
NITZSCHIA TABELLARIA GRUN.
Valve rhomboidal, inflated in the middle; apices produced; keel puncta extend in costæ across half of the valve, 7 in 10 µ; striæ transverse, about 22 in 10 µ. L. 20 µ.
Dimerogramma sinuatum Thwaites.
Nitzschia sinuata var. tabellaria (Grun.) V. H.