Sagittaria L.

1. Sagittaria L. View in CoL 2

Stock often stoloniferous and tuberiferous. Leaves aerial, floating or submerged. Flowers unisexual or polygamous, in umbels, racemes or panicles with female or hermaphrodite flowers at the base and male flowers above, or occasionally with the flowers all male or all female. Stamens usually numerous. Carpels numerous, spirally arranged, free, each with 1 ovule; styles apical or subventral. Fruitlets achenial, laterally compressed, obliquely obovate, the margins winged, with an apical or ventral beak.

1 Edit. V. H. Heywood. 2 By J. E. Dandy.

Several species from North America are cultivated for ornament, and two of these have recently become established in Europe. S. subulata (L.) Buchenau , Abh. Naturw. Ver. Bremen 2: 490 (1871), naturalized in a single locality in S. England, has glabrous dilated filaments, and leaves which are linear and submerged or may terminate in an elliptical to ovate-oblong floating blade. S. platyphylla (Engelm.) G.E. Sm. , Ann. Rep. Missouri Bot. Gard. 6: 55 (1895), naturalized in a single locality in N. Italy (Varese prov.), has pubescent, dilated filaments, lanceolate aerial leaves and the pedicels deflexed in fruit.

Literature: K. Rataj, Annot. Zool. Bot. (Bratislava) 76: 1-31

(1972); 78: 1-61 (1972).

1 Filaments of male flowers dilated, pubescent; bracts all ± connate 4. rigida

1 Filaments of male flowers linear, not dilated, glabrous; at least the lower bracts free

2 Leaves mostlyfloating,lineartooblongorovate-oblong, cuneate to rounded at the base or cordate with 2 short obtuse lobes; anthers yellow 2. natans

2 Leavesmostlyaerialandsagittatewith2 longacutebasal lobes

3 Fruitlets with a short, erect, apical beak; petals white, usually with a purple patch at the base; anthers usually purple 1. sagittifolia

3 Fruitlets with a ± elongated, horizontal, ventral beak; petals white, without a purple patch; anthers yellow 3. latifolia