Zygnema (zignema)

[NL. (Kützing, 1843), irreg. many-rayed chlorophyl-bodies near the central cell-nucleus, each containing a starch-granule, and the zygospore undivided, mostly contracted, and developed in the middle space between two united pairing-cells or in one or the other of the conjugating-cells. Several of the species are among the commonest of fresh-water algæ in both stagnant and running water, forming dense bright-green ma es. See cuts under chlorophyl and conjugation. cardiac.