284 



HENDEESON'S HANDBOOK OF PLANTS 



ONO 



tending to a considerable depth, which, on 

 hard soil, tends to break up the subsoil, and 

 loosen it for subsequent cultivation. It has 

 been grown in some parts of France, Ger- 

 many, and England for years, and has proved 

 a most valuable fodder plant, especially in 

 light, dry, sandy or calcareous districts in tiie 

 Southei-n and Western States. Owing to its 

 long descending roots it flourishes during 

 long continued droughts, and succeeds in 

 many situations where no other forage plant 

 would exist. It is moreover very nutritious, 

 and whether made into hay or fed green is 

 greatly relished by all domestic cattle. It 

 will crop from seven to ten years, according 

 to the nature of the soil, and its yield is 

 greatly increased by judicious top dressing. 

 Its culture is almost identical with that of 

 Alfalfa or Luzerne, which see. 



Ono'clea. From onos, a vessel, and kleio, to 

 close ; I'eferring to the singularly rolled up 

 fructification. Nat. Ord. Polyjiodiaceae.. 



A very distinct genus of Ferns, the principal 

 and perhaps the only species of which is O. 

 sensibilis, sometimes called the Sensitive 

 Fern, but having no other claim to this 

 name, beyond the fact of its speedily 

 withering when cut. It is a very common 

 Fern, found generally in moist or wet places, 

 along streams, etc. It is an excellent subject 

 for a shady place in the rock garden. 



Ono'nis. Kest-harrow. From onos, an ass, 

 and onemi, to delight; the ass delights to 

 browse on the herbage. Nat. Ord. Legu- 

 minosce. 



An extensive genus of small herbaceous 

 plants, common to Europe. A few species 

 are tender annuals from the Cape of Good 

 Hope. They have white, pink, or yellow 

 flowers, some of them very pretty, but best 

 suited to rough, waste places. They are 

 easily grown from seed, and will adapt them- 

 selves to any place given them. 



Onopo'rdon. Cotton Thistle. From onos, an 

 ass, and perdo, to destroy ; referring to the 

 supposed effects on the ass. Nat. Ord. Com- 

 positce. 



0. Acanthium, the supposed Scotch Thistle, 

 is a native of Europe, but has become natural- 

 ized in many parts of the United States. It 

 grows from six to eight feet high, and is one 

 of the most shoAvy of the Thistle family. 

 According to common tradition, the Danes or 

 Norsemen, wliile invading Scotland, came 

 upon the Scots, unperceived at midnight, and 

 halting while their spies were thrown for- 

 ward to discover the undefended points of 

 their enemy's camp, one of them chancing to 

 tread upon a Thistle of this species, uttered 

 a loud cry of pain, Avhich roused the Scots to 

 their danger, who at once attacked and re- 

 pelled the invaders, gaining a complete 

 victory ; and henceforth they adopted the 

 Thistle as the national emblem. In 1540 

 James V. instituted an order of knighthood 

 called the Order of the Thistle. See Scotch 

 Thistle. 



Ono'seris. From onos, an ass, and seris, Endive ; 

 a salad foi- asses. Nat. Ord. Composites. 



A genus of about a dozen shrubs or herbs, 

 natives of the Andes and tropical South 

 America. The leaves of O. adpressa are over 

 three inches long, and are pure white and 



OPH 



cottony beneath. Introduced in 1830, under 

 the name of Centroclinium. 

 Ono'sma. Golden Drop. From onos, an ass, 

 and osme, smell ; said to be grateful to that 

 animal. 



A genus of Boraginacem, consisting of 

 nearly seventy species, only a few of which 

 are in cultivation. They are found in northern 

 Africa, southern Europe, and west and central 

 Asia. 0. stellatum, and its variety 0. s. tauricum, 

 with yellow flowers, are the most showy, and 

 should have a well-drained sunny exposure in 

 the rock garden, or herbaceous border. 



Onosmo'dium. So called from its similarity to 

 Ouosma. Nat. Ord. Boraginacece. 



A small genus of hardy herbacous peren- 

 nials, only two of which, O. Carolinianum and 

 O. Virginianum both with yellowish-white 

 flowers, and natives of the United States, are 

 in cultivation. 



Ony'chium. From onyx, a claw ; shape of the 

 lobes of the fronds. Nat. Ord. Polypodiacem. 

 A small genus of very elegant Ferns found 

 in Japan, Africa, Australia, and the East 

 Indies. A few of the species are under cul- 

 tivation, and among them 0. Japonicum, a 

 delicate, fennel-like Fern, fragile, fairy-like, 

 yet one that succeeds well with the most 

 ordinary green-house treatment. It requires 

 shade, and is propagated from spores or by 

 division. Introduced in 1864. Syns. 0. 

 Capetise and O. lucidum. 



Opaque. When the surface is dull, or not at all 

 shining. 



Opera Girls. See Manlisia saltatoria. 



Opercula'ria. From oj)erculum, lid ; referring to 

 the shape of the calyx. Nat. Ord. Rubiacece. 



A genus of very })retty Australian green- 

 house shrubs or herbs, sometimes twining. 

 The species, of which only two are in cultiva- 

 tion, succeed best in a compost of sandy loam 

 and leaf mould, and are propagated by seeds 

 sown in heat in spring, or by cuttings of the 

 young shoots. 



Operculum. The lid of anything, as in the 

 pitcher of Nepenthes ; more especially the lid 

 of the spore-cases of Urn-mosses. 



Ophe'Ua. From Opheleia, serviceable ; plants 

 useful in medicine. Nat. Ord. Gentianacem. 



This genus is composed of one species, a 

 pretty little annual, with starry pink flowers, 

 allied to the Gentian. Seeds should be sown 

 early in the hot-bed or in tiie green-house, and 

 planted out as soon as the border is ready for 

 tender plants. It is a native of the East 

 Indies, and was introduced in 1836. Syn. 

 Swertia. 



Ophiocau'lon. From ophis, a serpent, and 

 kaulon, a stem; in reference to its climbing 

 habit. Nat. Ord. PassifioracexB. 



A small genus of plant-stove, climbing, her- 

 baceous plants, natives of tropical Africa, 

 Natal, and Madagascar. O. Cissampeloides, 

 introduced from western Afi-ica in 1871, is a 

 green-house climber with orbicular or cordate, 

 glaucous leaves two to three inches long, 

 often mottled with white. It is closely allied 

 to Modecca, and is often found in cultivation 

 under the name of Passiflora marmorata. 



Ophioglo'ssum. Adder's Tongue. Fromop^iios, 

 a snake, and glossa, a tongue ; referring to the 

 shape of the spike of fructification. 



