Flora of New Zealand Series

Slender glab. branching herb up to 15 cm. or more tall, forming dense or loose tufts. Lvs opp., 0·5-2.5 cm. long, linear-lanceolate to spathulate to narrow-ovate, acute or subacute. Fls axillary or terminal, solitary or in 2-3-(5)-fld cymes, ± 2-3 mm. diam.; petals slightly > sepals, greenish white. Capsules hardly = sepals; seeds 3, c. 1 mm. diam., black.

DIST.: N., S., St., A., Ant., M. Coastal to lowland to subalpine streams and pools, moors, damp screes and herbfield from lat. 39° southwards.

Forms growing in water are us. elongated. The seeds differ in testa characters on different plants, but the material available is not sufficient definitely to correlate seed characters with the various If and other morphological characters, or with geographical distribution. The testa characters are constant for any one plant: (a) seeds distinctly but finely tuberculate, somewhat shining to dullish, (b) seeds finely reticulate, glossy. The relation of these N.Z. forms to M. lamprosperma Cham., M. rivularis Gmel., etc., needs detailed study.