Family Description: Aquatic or marsh herbs, usually perennial. Leaves alternate or basal, sheathing at the base. Flowers hermaphrodite or unisexual, usually bracteate and verticillate in pedunculate umbels, racemes or panicles, occasionally long-pedunculate in leaf-axils. Sepals 3. Petals 3, usually larger than the sepals, often fugacious or deciduous. Stamens 3-numerous, with elongated filaments; anthers opening by longitudinal slits. Carpels 3-numerous, spirally arranged or whorled, free or connate at the base; ovules 1-many; styles apical or subventral. Fruit a group of achenes, drupelets or follicles; seeds without endosperm; embryo horseshoe-shaped.
Family Description: Submerged or floating aquatic herbs, sometimes marine. Leaves alternate, opposite or verticillate, sheathing at the base or with nodal scales. Flowers hermaphrodite or unisexual, 1 or more together in spathes composed of 1 or 2 free or connate bracts. Sepals 3. Petals 3 or 0. Stamens 2-15, free or connate at the base, occasionally some staminodal; filaments elongated or absent; anthers 2-thecous, opening by longitudinal slits. Ovary syncarpous, inferior, often attenuated into a filiform beak. ovules on parietal, sometimes intruded placentas; styles 3-15 Fruit dehiscing irregularly or splitting stellately into valves; seeds without endosperm; embryo straight.
Family Description: Aquatic or marsh herbs; stems stout. Leaves basal, alternate, linear, sheathing at the base. Flowers hermaphrodite or unisexual, ebracteate, in pedunculate racemes or spikes. Perianth of 2-6 sepaloid segments. Stamens 3 or 6, often adnate at the base to the perianth-segments; anthers sessile, 2-thecous, opening by longitudinal slits. Carpels 3 or 6, free or connate, each with 1 ovule; styles short or stigmas sessile. Fruit apocarpous or syncarpous, the fruitlets separating when ripe; seeds with or without endosperm; embryo straight.
Family Description: Perennial, rhizomatous, aquatic herbs. Leaves petiolate. Inflorescence a spike or raceme, subtended by a spathe-like bract. Flowers hermaphrodite, more or less zygomorphic, usually ephemeral. Perianth-segments 6, petaloid, connate at least at the base. Stamens 3 or 6. Ovary superior, 3-locular, or 1-locular by abortion, 1- to many-seeded. Fruit a capsule, tightly invested by the persistent perianth.
Family Description: Submerged, marine perennial herbs with creeping rhizomes. Leaves basal, alternate, linear, sheathing at the base. Inflorescence of 1 or more aggregated spikes borne on an elongated peduncle and subtended by leaf-like bracts. Flowers hermaphrodite or the uppermost with a reduced gynoecium, ebracteate. Perianth absent. Stamens 3; anthers sessile, opening by longitudinal slits. Carpel 1, ovule 1. Fruit a berry; seeds without endosperm; embryo straight.
Family Description: Aquatic herbs, submerged or with floating leaves, occasionally subterrestrial. Stems elongated. Leaves alternate or opposite (rarely in whorls of 3), sheathing at the base. Flowers hermaphrodite, ebracteate, in pedunculate spikes. Perianth of 4 unguiculate, sepaloid segments. Stamens 4, adnate at the base to the perianth-segments; anthers sessile, opening by longitudinal slits. Carpels (1-)4, free or shortly connate at the base, 1-ovulate; styles usually short. Fruitlets drupaceous or achenial. Seeds without endosperm; embryo unciform or spiral (coiled more than 1 complete turn).
Potamogeton helveticus W.Koch Potamogeton pectinatus L.
Fennel Pondweed, Ribbon weed, Sago Pondweed
Maltese name not known
Normal Profile with 4 images.
RUPPIACEAE Horan. ( Ditchgrass Family )
Family Description: Submerged, perennial herbs of saline water. Leaves narrowly linear, sheathing at the base. Flowers hermaphrodite, small, ebracteate, in 2-flowered, pedunculate spikes; peduncles slender, often accrescent in fruit. Perianth absent. Stamens 2; anthers sessile, opening by longitudinal slits. Carpels 4(-10), free, with 1 ovule, sessile in flower but usually becoming slender-stipitate in fruit. Fruitlets indehiscent; seeds without endosperm.
Family Description: Monoecious. Flowers usually surrounded by hairs or scales (sometimes interpreted as perianth-segments), in 2 dense, superposed, cylindrical, spike-like partial inflorescences, the female below, the male above. Male flowers with simple or forked hairs or linear-lanceolate scales, or naked; stamens in clusters of 1-3 (-8); filaments often irregularly united. Female flowers on branched stalks, with hairs and sometimes also with scales, the branches with sterile flowers. Ovary superior, 1-locular, on a hairy stalk; style persistent; ovule solitary. Fruit dry, usually dehiscent.
Family Description: Perennial, submerged marine herbs. Rhizome creeping, with long internodes, bearing at each node 2 or more unbranched roots and a leaf with a short shoot in its axil. Short shoots with several distichous, linear leaves with compressed, sheathing bases. Flowering stems lateral or terminal. Inflorescence enclosed in the sheathing base of a spathe. Flowers with 1 dorsifixed, sessile stamen and 1 unilocular ovary with a style and 2 long, filiform stigmas, arranged alternately on the margin of the flattened axis; perianth absent. Pollen-grains filiform. Ovule 1.