

AN ENCYCLOPAEDIA OF HORTICULTURE. 



481 



Olea continued. 



O. verrucosa (warted). /. in axillary panicles, scarcely 

 shorter than the leaves. April, fr. sub-globose. I. linear- 

 lanceolate, sub-sessile, attenuated at both ends, callous-apicu- 

 late, entire, glabrous above, scaly beneath. Cape of Good Hope, 

 1814. 



OLE ACE JB. An order of erect or climbing shrubs 

 or trees, inhabiting the temperate and warmer regions 

 of the globe. Flowers hermaphrodite, rarely dioecious 

 or polygamous, regular ; calyx campanulate, four or 

 many-toothed or lobed, rarely none ; corolla gamo- 

 petalons, salver or funnel-shaped, or campanulate; lobes 

 or petals four, rarely five or six, sometimes absent ; in- 

 florescence sometimes centrifugal, dichotomously cymose, 

 sometimes trichotomously paniculate, mostly or totally 

 centripetal, or the branchlets ultimately centrifugal- 

 cymose; panicles, or cymes, loose, or in contracted fas- 

 cicles, axillary or terminal. Fruit indehiscent, or a loculi- 

 cidal capsule, a berry, or a drupe. Leaves opposite, rarely 

 alternate or whorled, simple or pinnately three or few- 

 foliolate, entire or toothed ; stipules none. Olive oil is 

 expressed from the pericarp of the drupe of Olea 

 europcea, and the unripe drupe, macerated in brine, is 

 eaten. Ash-wood (Fraxinus) is invaluable for its light- 

 ness, flexibility, and strength ; and a sugary juice, 

 Manna, is produced by F. Ornus and some other 

 species ; while the bark of the common Ash (F. excelsior) 

 has been proposed as a substitute for quinine. The 

 order contains eighteen genera and about 280 species. 

 Illustrative genera are : Fraxinus, Jasminum, Olea, and 

 Syringa. 



OLEANDER. See Neriuin Oleander. 



OIiEANDRA (from Oleander, which plant 0. nerii- 

 formis is thought to resemble). ORD. Filices. A 

 small genus (about half-a-dozen species) of stove Ferns, 

 almost restricted to the tropics. They are distinguished 

 from Nephrodium mainly in habit, with wide-creeping, 

 scandent shoots, jointed stems, and entire, lanceolate- 

 elliptical fronds. Sori round, inserted in a row near 

 the base, or below the centre of the compact, free vein- 

 lets ; involucre reniform. The species in cultivation 

 may be used for pillar plants. A wire cylinder should 

 be made around the pillar, and filled up with fibrous 

 peat and sphagnum. The creeping rhizomes should then 

 be laid over the surface, and fastened 'by means of small 

 wire or wooden pegs. Large pots or pans may also be 

 utilised, on which to build fibry peat in the shape of a 

 cone or ball, covering the surface with rhizomes in the 

 same way. Thus treated, specimens of almost any size 

 may be, in course of time, obtained. For general cul- 

 ture, nee Ferns. 



O. articulata (jointed).* shoots firm, sub-erect, wide-climbing, 

 scaly, sti. scattered, sometimes opposite, but not whorled, lin. 

 to 2in. long, with the joint close to the base, fronds bin. to 12in. 

 long, liin. to 2in. broad, sori in two irregular rows, often some 

 distance from the midrib. Natal, Mascarene Islands, &c. A fine, 

 evergreen species. 



O. hirtella (slightly hairy). A form of 0. neriiformis. 



O. mtiscefolia (Musa-leaved). shoots firm, wide-climbing, clothed 

 with aclpressed scales, sti. Jin. to lin. long, jointed close to the 

 base, fronds (tin. to 12in. long, lin. to Hin. broad, narrowed 

 gradually towards both ends, sori in two irregular rows near 

 the midrib ; involucre oblique. Ceylon and Malayan Islands. 



O. neriiformls (Oleander-like).* shoots woody, sub-erect, scaly. 

 sti. Jin. to lin. long, with the joint just below the middle, fronds 

 6in. to 18in. long, Jin. to 14m. broad, scattered or in opposite 

 pairs, or often in terminal whorls, narrowed gradually towards 

 both ends, sori in two rather irregular rows, near the midrib ; 

 involucre oblique. Tropics. A very handsome species, of which 

 0. hirtella is merely a form. 



O. nodosa (knotty).* shoots trailing horizontally, densely clothed 

 with linear-subulate, spreading scales, sti. scattered, 2in. to 

 6in. long, often ebeneous, articulated not far from the base. 

 fronds 6in. to 12in. long, liin. to 2iin. broad, the apex acuminate, 

 the edge entire, sori scattered, placed nearly all in the inner half 

 of the frond ; involucre one-third of a line broad. West Indies, 

 &c A beautiful, free-growing species, distinguished from all the 

 others by its trailing shoots, satiny gloss, and copious, irregularly - 

 scattered sori. 



Vol. II. 



Oleandra continued. 



O. Wallichli (Wallich's). shoots trailing horizontally; scales 

 spreading, ferruginous, sti. close or scattered, Jin. to 2in. long, 

 jointed close to the base, fronds 6in. to 12in. long, iin. to liin. 

 broad, the apex acuminate ; rachis naked or scaly, sori in single 

 rows close to the midrib ; involucre ciliated. North India (up to 

 7000ft. altitude). 



OLEARIA (from Olea, an Olive-tree ; in allusion to 

 the resemblance to that tree existing in some of the 

 species). STN. Eurybia. ORD. Composite. A large 

 genus of greenhouse or hardy shrubs, sometimes arbo- 

 rescent, sub-shrubs, or rarely branched herbs. Eighty- 

 five species have been described ; of these, sixty-three are 

 Australian, and the rest natives of New Zealand and the 

 adjacent islands. Flower-heads rather large, mediocre 

 or small, solitary, corymbose or paniculate ; ray-florets 

 white or blue ; disk yellow, or rarely bluish-purpla ; in- 

 volucre ovoid, campanulate, or sub-hemispherical ; recep- 

 tacle flat or slightly convex, foveolate. Leaves alter- 

 nate or rarely opposite, penniveined or one-nerved, entire 

 or dentate. Olearias make excellent plants for the cool 

 conservatory where they thrive best when planted out 

 or for clothing dwarf walls, &c. Some of them 0. 

 Haastii, for instance make beautiful bushes in the open 

 shrubbery border, and are quite hardy in most places. 

 The species are readily propagated by means of half- 

 ripened young shoots, inserted in sandy soil, under a bell 

 glass, and shaded. They succeed in almost any soil. 

 Probably the species here described are the only ones 

 yet introduced. 



O. dentata (toothed).* fl. -heads rosy-white, about liin. in diameter, 

 in terminal, erect or spreading corymbs. Spring. I. petioled, 

 very variable, liin. to 2in. long, elliptic-ovate or cordate-ovate, 

 obtuse, crenated. Australia. Nearly hardy shrub, with branches, 

 leaves (beneath), and inflorescence densely tomentose. (B. M. 

 5973.) 



O. Forsteri (Forster's). fl.-heads white, fascicled, and sessile on 

 the branches of the panicle ; corymbs longer than the leaves, 

 many-headed. Summer. I. 2in. to Sin. long, oblong, obtuse ; 

 margins undulated ; both surfaces reticulated, lower white with 

 down ; petioles iin. to lin. long. New Zealand, 1866. A small, 

 hardy tree. 



O. furfuracea (scurfy), fl.-heads Jin. in diameter, numerous, in 

 large, branched, loose, spreading corjrmbs. 1. liin. to 2Jin. broad, 

 ovate-oblong, obtuse, waved, rarely sinuate-toothed, rounded and 

 unequal at base, reticulated above ; netioles iin. to lin. long. 

 Branches terete, velvety. /(. 10ft. to 15ft. New Zealand. Hardy 

 tree. 



FIG. 726. OLEARIA GONNIANA, showing Flowering Branch ; 

 (1) Branchlet, and (2) Flower-head. 



O. Gunnlana (Gunn's).* jl.-heads white, borne in great profusion, 

 about Jin. in diameter. September. I. oblanceolate, coarsely 

 toothed, and hoary on the under surface. Branches hoary, h. 3ft. 



