2410 



OROBANCHE 



see. In Orobanche, the calyx is deeply divided into 2 

 or 4 pointed sepals; corolla broadly tubular or bell- 

 shaped, often curved, more or less 2-lipped; stamens 4, 

 m 2 pairs; ovary 1 -celled. About 100 species, if 

 Aphyllon and some others are included, widely dis- 

 tributed, a number of them in Eu. They are scarcely 

 horticultural subjects, although it is possible to grow 

 them. Writing in The Garden (59, p. 93), Francis D. 

 Homer, says that he was able to grow O. speciosa 3 ft. 

 8 in. high, with many showy fls., and that it began to 

 bloom at 8 in. high. He establishes them on the roots 

 of beans. He grows 3 or 4 beans in a 7-in. pot, and when 

 they are 2 or 3 Ivs. high and the roots well around the 

 pot, orobanche seeds are sown over the damp surface. 

 Before the beans are pot-bound, they are planted out 

 with the ball of earth unbroken. The orobanche heads 

 will appear in July. It is essential that the beans do not 

 get into bloom before the seed of the parasite is sown, 

 otherwise it will not get a sufficiently early start to 

 ripen. When fls. of the parasite have turned into shades 

 of brown and the stems have fallen, the plants are 

 stored for seed, which is minute. L H B 



OROBUS (an old Greek name). Leguminbsse. A 

 genus not now kept separate, and referred mostly to 

 Lathyrus, from which it was distinguished largely by 

 its erect habit and lack of tendrils; some of the species 

 now go to Vicia. Five species-names were found by 

 Beal (Study of Genus Lathyrus, Cornell Bulletins) to 

 be offered by American seedsmen: 0. niger (=Lathy- 

 rus niger), 0. vernus (^Lathyrus vernus), O. lalhyroides 

 (probably = Vicia oroboides), and 0. albus and 0. superbus 

 which are probably horticultural forms of Lathyrus 

 vernus. Abroad there are also listed 0. aurantiacus, 

 which may be Vicia aurantia; 0. canescens, 0. azureus, 

 O. varius, 0. Smithii with "creamy yellow fls., dwarf 

 grower," which probably belong in Lathyrus. 



ORONTIUM (one of many names arbitrarily applied 

 by Linnaeus; he probably had in mind some water 

 plant growing in the Syrian river Orontes). Aracese. 

 A hardy native aquatic plant, which bears in early 

 spring yellow "clubs" on white stalks. The "club" is a 

 cylindrical spadix 1 to 2 inches long. 



Spathe usually soon deciduous; fls. hermaphro- 

 dite, covering the whole spadix; sepals scale-like, 

 imbricated upon the ovary, usually 4 in the upper and 6 

 in the lower fls.; ovary 1 -celled; ovule solitary, semi- 

 anatropous: fr. a green utricle. One species, found 

 in swamps and pools from Mass, to Fla., mostly near 

 the seacoast, but extending as far inland as Cent. Pa. 

 and La. . 



aqu&ticum, Linn. GOLDEN CLUB. Lvs. ascending 

 or floating, according to the depth of the water, oblong- 

 elliptic, no distinct midrib, but numerous parallel veins; 

 blade 5-12 x 2-5 in.; stalk 4-20 in. long: scape U-2 ft 

 long. B.B. 1:364. L.B.C. 5:402. R.H. 1888:85. Gn. 

 27, p. 213. G.M. 54:247. The foliage is handsome, 

 dark velvety green above, silvery below. The plant is 

 very strong and deeply rooted, growing in water 10-18 

 in. deep. On account of its firm hold on the soil it may 

 be planted in swifter water than most aquatics. It has 

 the fault of being difficult to eradicate when firmly 

 established. F w BARCLAY 



OROXYLUM (Greek, a mountain tree; nevertheless it 

 grows anywhere from sea-level to an altitude of 3,000 ft.) . 

 Also written Oroxylon. Bignoniacex. An ornamental 

 tree from S. Asia, with large opposite twice- or thrice- 

 pinnate Ivs.: fls. in terminal panicles; calyx leathery, 

 campanulate, truncate or shortly toothed; corolla cam- 

 panulate, white or purplish with 5 crisped and toothed 

 lobes imbricate in bud; stamens 5, slightly exserted; 

 disk large, fleshy: fr. linear, septicidally dehiscent; seeds 

 broadly elliptic, compressed with a broad transparent 

 wing. A very striking plant with bold much-divided 



ORTHROSANTHUS 



glossy foliage and ample terminal panicles of large 

 white or purple fls. followed by very long and narrow 

 pendulous caps. It is cult, outdoors in Calif, and in 

 Eu. in greenhouses. Demands rich soil. Prop, by seeds 

 and by cuttings with bottom heat. 



Indicum, Vent. (Calosdnthes indica, Blume). Tree, 

 to 40 ft.: Ivs. 2-4 ft. across; Ifts. ovate, entire, glabrous' 

 about 5 in. long: racemes peduncled, to 10 in. long; fls' 

 2^ in. long and 2-3K in. across: caps. 1-3 ft, long and 

 2-3 in. wide, compressed. India to Cochin-China and 

 Malaya. Wight, Icon. 1337. 



O. flavum, Rehd.=Radermachia pentandra. 



ALFRED REHDER. 



ORPINE, or STONE CROP: Sedum, particularly S. Telephium. 

 ORRIS-ROOT, or IRIS-ROOT: Iris florentina and others. 



ORTHOCARPUS (Greek, straight fruit, which dis- 

 tinguishes this genus from Melampyrum). Scrophu- 

 laridcese. Annual and perennial herbs, which may be 

 transferred to gardens: Ivs. alternate, incised, those in 

 the infl. sometimes colored : fls. mostly white, yellow or 

 cream-colored, sometimes marked, in spikes; corolla 

 tubular, 2-lipped; calyx 4-cleft; stamens 4. Species 

 about 30, W. N. Amer., and 1 in S. Amer. 0. pur- 

 purdscens, Benth., is something like the painted cup 

 (Castilleja). It is a Calif ornian annual, growing a foot 

 high, with gaudy bracts, and crimson or purple corolla 

 1-1 l /i in. long, the lower lip white-tipped and with 

 yellow or purple markings. It is a common and showy 

 plant growing in the Sierra Nevada foothills, the 

 interior valleys and Coast ranges. This plant was 

 offered in 1891. L H B 



ORTHOSIPHON (name refers to the straight tube). 

 Labiatse. Annual or perennial herbs sometimes sub- 

 shrubs, of more than 100 species in the tropics from 

 Afr. to Austral., little known in cult.: Ivs. opposite or 

 whorled, glandular-dotted: infl. terminal, sometimes 

 with colored bracts at top, each whorl 2-6-fld., fls. 

 variable in size; calyx unequally 5-toothed; corolla- 

 tube mostly surpassing the calyx; corolla-limb 2-lipped, 

 the upper lip shortly 3-4-lobed and the lower concave 

 or boat-shaped; stamens 4, exserted; ovary deeply 

 4-lobed, the style filiform and exserted. 0. stamineus, 

 Benth., is probably the species most likely to be found 

 in glasshouses: 1-2 ft., glabrous or pubescent, the st. 

 4-angled: Ivs. ovate, acuminate, coarsely toothed, 

 petioled: fls. white or purplish, about 1 in. long, the 

 corolla-tube thrice longer than calyx; stamens much 

 exserted. India. B.M. 5833. G.Z. 29:145. 



L. H. B. 



ORTHROSANTHUS (Greek, morning flower; because 

 the fls. open in the morning and fade before noon). 

 Iridacese. Small plants for indoor use, listed with 

 dealers among bulbs, bearing bright flowers on a scape 

 arising from the clump of narrow leaves. 



Orthrosanthus is a genus of 9 or 10 species, from Trop. 

 or extra-Trop. Amer. and Austral. Rootstock short: 

 Ivs. firm, linear, equitant: clusters many-fld., panicled; 

 fls. pale blue; pedicels so short that the caps, is not 

 protruded from the spathe; perianth-tube very short 

 or none; segms. oblong, nearly equal, spreading; fila- 

 ments free or connate only at the base; ovary 3-celled; 

 ovules many, superposed; style-branches alternating 

 with the anthers: seeds minute. Very near Sisyrinchium 

 which is a more variable genus, and has longer pedicels. 



multiflorus, Sweet (Libertia azurea, Hort. Sisyrin- 

 chium cydneum, Lindl.). Lvs. a dozen or more, 1-1 /^ 

 ft. long, J/g-^in. wide: panicle 4-6 in. long: caps, 

 obtuse. S. and W. Austral. L.B.C. 15:1474. B.R. 

 1090. 0. multiflorus is a charming plant something 

 like blue-eyed grass or sisyrinchium. It has a tuft of 

 grassy foliage a foot or two high, and sky-blue 6- 

 parted fls. an inch or more across, which open one after 



