394. Elodea (Anacharis). - Aquatic, submerged; plant dioecious; leaves linear, opposite or in whorls; flowers small, male rare, female long-stalked; calyx 3-partite; spathe 2-fid.

395. Hydrocharis. - Aquatic plant, dioecious; leaves reniform, floating; flowers large; calyx 3-partite; petals 3; males with stamens, 9-12 in 3 rows, and 3 functionless styles; female with 3 functionless filaments, 3 scales, and 6 styles; capsule 6-celled.

396. Stratiotes. - Plant submerged and floating alternatively, dioecious; leaves ensiform, serrate; flowers white, large; perianth 6-partite, in 2 rows; male with 12 stamens, female with 6 2-fid styles; berry 6-celled.

Order 79. Orchidaceae

397. Malaxis. - Herbaceous, leafy; perianth spreading; lip superior; spur o; rostellum short; pollen-masses connected above; column short.

398. Liparis. - Herbaceous, leafy; perianth spreading; lip inferior; column slender; rostellum o.

399. Corallorrhiza. - Saprophyte, leafless; perianth meeting together; lip inferior, white with purplish markings; spur o; column long; rostellum o.

400. Neottia. - Saprophyte; brown scales in place of leaves; perianth hooded; pollen powdery; spur o; lip turned down, yellowish brown, 2-lobed, enlarged below; rostellum flat.

401. Listera. - Leaves in pairs, sub-opposite; perianth spreading; lip turned down, linear, free; pollen powdery; rostellum leaf-like, arching over stigma.

402. Spiranthes. - Leaves several; flowers spiral on stalk; perianth gaping; lip inferior with fleshy projections below, clawed; lateral sepals coloured; rostellum straight; 2-fid at length.

403. Goodyera. - Leaves several; perianth gaping; lip swollen below, entire, free; rostellum 2-partite; pollen-grains cohering.

404. Epipogium. - Saprophyte, brown, leafless; perianth spreading, lip superior; ovary not twisted; pollen granular.

405. Cephalanthera. - Stem leafy; flowers erect, in a spike; perianth meeting; column long; ovary twisted; beak of style short.

406. Helleborine (Epipactis). - Stem leafy; flowers in raceme, drooping; perianth spreading; lip interrupted; rostellum short; column short; ovary straight, stalk twisted.

407. Orchis. - Perianth hooded; lip 3-lobed, spurred; spur long; pollen glands in one pouch.

408. Aceras. - Perianth hooded; lip pendant, 3-lobed; spur o; pollen glands in 1 pouch.

409. Ophrys. - Perianth spreading; lip lobed; spur o; pollen glands in 2 pouches.

410. Herminium. - Perianth spreading, bell-shaped; lip petaloid; spur o; lip 3-lobed; pollen glands naked, exserted.

411. Habenaria. - Perianth gaping, hooded; lip spurred; spur long or short; lip 3-lobed or entire; pollen glands naked.

412. Cypripedium. - Perianth spreading; lip large, saccate; anthers 2 (1 in rest of Orchids); column 3-fid above.

Order 80. Iridaceae

413. Iris. - Perianth regular, 6-cleft, segments unequal, alternate ones reflexed; stigmas 3, petaloid; ovary 3-celled.

414. Hermodactylus. - As 413, rootstock digitate; ovary I-locular.

415. Crocus. - Perianth regular, funnel-shaped; tube long, segments equal; stigma 3-fid or 3-partite.

416. Romulea. - Perianth regular, 6-cleft, segments equal; tube short; styles 3, 2-fid; lobes slender.

417. Sisyrinchium. - Perianth 6-cleft, segments subequal; tube short; styles 3, short, entire, slender; filaments united below.

Order 81. Amaryllidaceae

418. Narcissus. - Perianth-mouth with circular corona (crown); limb 6-partite, segments equal; stamens included, unequal.

419. Galanthus. - Perianth without corona, 6-partite, segments unequal. in 2 series, outer larger; stamens equal.

420. Leucojum. - Perianth bell-shaped, without corona; segments equal with thickened tips; stamens equal.

Order 82. Dioscoreaceae

421. Tamus. - Twining plant, dioecious, stem twining to left; perianth bell-shaped, small, limb 6-partite; 6 stamens; in female, perianth adnate to ovary; fruit a berry.

Order 83. Liliaceae (and Asparagaceae and Melanthaceae)

422. Ruscus. - Shrub; cladodes in axils of minute scales; plant dioecious; stamens 3; filaments united below; berry I-celled, 2-seeded.

423. Asparagus. - Herbaceous; stem branched; flowers axillary; perianth 6-partite, tubular below; stamens 6; filaments free; stigmas 3, reflexed.

424. Polygonatum. - Stem simple; leaves many; flowers axillary; perianth tubular, 6-cleft, deciduous at length; berry with 1-2-seeded cells.

425. Maianthemum (Unifolium). - Stem simple; leaves 2; flowers in terminal racemes; perianth 4-partite; stamens 4; berry 2-celled.

426. Convallaria. - Stem simple; leaves radical; flowers in raceme; perianth globular, 6-partite; berry with 1-seeded cells.

427. Simethis. - Rootstock bulbous; flowers jointed on pedicels, purple outside, white within; perianth-segments 6, spreading; filaments bearded; anthers attached by back.

428. Allium. - Flowers in umbel; spathe of 1 or 2 leaves; perianth-segments 6, spreading; anthers attached by backs.

429. Muscari. - Leaves radical; perianth-segments coherent below; perianth globose, mouth narrowed; 6-cleft.

430. Scilla (Endymion). - Flowers blue or pink, in racemes; perianth-segments 6, spreading; anthers attached by backs.

431. Ornithogalum. - Flowers white or greenish; perianth segments 6; persistent; stamens on receptacle; anthers attached by backs.

432. Lilium. - Flowers on leafy scape, few, nodding, panicled; nectaries o; perianth spreading or turned back; anthers attached above the base; seeds flat.

433. Fritillaria. - Flowers nodding, large, solitary, red or white, chequered; nectary oblong; perianth deciduous; anthers attached above their base.

434. Tulipa. - Flowers large, erect, solitary, yellow; nectaries o; perianth deciduous; anthers erect.

435. Gagea. - Flowers in umbel, yellow, small; nectaries o; leaves 1-2, linear; anthers erect; perianth-segments 6, spreading; persistent.