The chromatophores consist of circular and compressed or irregular flat granules which lie along the wall of the cell.
MELOSEIRA DISTANS (EHR.) KUETZ.
Frustules cylindrical, slender, with two furrows, one on each side of the suture; valve in zone view with fine puncta in longitudinal rows; puncta in valve view scattered. L. 7-10 µ.
Meloseira nivalis Wm. Sm.
Coscinodiscus minor Wm. Sm.
Fresh water. Fossil in New England deposits.
Pl. [1], Figs. 8 and 9.
Note.—In all species of Meloseira, as well as Gaillonella and Lysigonium, the frustules are so closely coherent that when the filaments are broken entire frustules are less frequently found than a union of two valves of contiguous frustules.
MELOSEIRA GRANULATA (EHR.) RALFS
Frustules cylindrical, robust, 5-18 µ in diam., with large granules in longitudinal, sometimes spiral, lines, variable in size and arrangement in the same filament. Valve in valve view with scattered puncta. Variable in relative width and length, passing to M. crenulata.