Montia Montia, L.

1. M. fontana L. , Sp. Pl. 87 (1753)

( M. minor C. C. Gmelin , M. rivularis C.C. Gmelin , M. verna Necker ).

Annual or perennial, with weak branching stems up to 50 cm or more in water, but short and erect, more or less caespitose, on land. Leaves 3-20 mm, usually narrowly spathulate. Flowers c. 2 mm, very inconspicuous, in small terminal cymes often overtopped by non-flowering branches. Capsule 1 - 5-2 mm; seeds usually 3. 2« = 18, 20. In water, or on mud or seasonally wet open ground, usually calcifuge. Most of Europe, except the south-east. All except Al Az BI Cr Rs (W, K, E) Tu.

A very variable species, in which the seed characters show correlation with geographical distribution and, less satisfactorily, with habit and habitat differences. Four subspecies can be recognized:

1 Ripe seeds smooth, shining (a) subsp. fontana 1 Ripe seeds dull or somewhat shining, with at least some low tubercles on keel

2 Ripe seeds dull, entirely covered with broad obtuse tubercles; usually annual, with erect caespitose stems, on damp sandy ground (d) subsp. chondrosperma

2 Ripe seeds somewhat shining, tubercles confined to keel;

annual or perennial, of varied habit 3 Ripe seeds with 3-4 rows of long acute tubercles on keel

(c) subsp. amporitana 3 Ripe seeds with variably developed broad low tubercles on

keel (b) subsp. variabilis