EUNOTIA LUNARIS (EHR.) GRUN.
Frustules sessile, solitary or in clusters. Valve arcuate, narrow, attenuated toward the apices, which are sometimes slightly rostrate or rostrate-capitate; transverse striæ, 14 in 10 µ, punctate.
Very common in ditches, especially in the spring. Variable in length.
Pl. [12], Figs. 24 and 25.
EUNOTIA HEMICYCLUS (EHR.) RALFS
Valve semicircular, with obtuse apices; striæ transverse, punctate; terminal nodules minute and indistinct.
Hammonton Pond, N. J. Rare.
Pl. [12], Fig. 23.
The genus Pseudo-Eunotia was created by Grunow for forms like Eunotia, but without terminal nodules. As, however, in E. lunaris and E. hemicyclus nodules are evident, although not so large as in many species, I include these two forms as heretofore under Eunotia.
EUNOTIA BICEPS EHR.