AN ENCYCLOPEDIA OF HORTICULTURE. 



499 



Onychium continued. 



linear, opposite, pressed down over the sori, the edge 

 nearly or quite reaching the midrib. Only two species 

 have been introduced; both thrive in a compost of peat, 

 loam, and sand. For general culture, see Ferns. 



O. auratum (golden).* sti. 6in. to 12in. long, stout, erect, naked. 

 fronds 1ft. or more long, 6in. broad, ovate, quadripinnatifid ; 

 lower pinnae 4in. to 6in. long, sub-deltoid, erecto-patent ; pinnules 

 and segments numerous, usually deltoid ; ultimate divisions of 

 the sterile frond often obovate-cuneate, tritid at the apex, not 

 more than one line long, coriaceous in texture ; those of the 

 fertile frond pod-like. Kachis and both surfaces naked; the 

 membranous involucres and copious sori a rich golden-yellow. 

 Himalayas. Stove. 



O. capense (Cape). A garden synonym of 0. japonieum. 



O. japonieum (Japanese).* sti. 6in. to 12in. long, stout, erect, 

 naked, fronds 1ft. or more long, 6in. broad, ovate, quadripin- 

 natifid ; lower pinnse 4in. to 6in. long, lanceolate- 

 deltoid ; pinnules and segments numerous, usually del- 

 toid, the copious, linear-mucronate, ultimate divisions 

 one and a-nalf to two lines long, nearly uniform in 

 the barren and fertile fronds, sori brown. Japan, China, 

 &c. Greenhouse or nearly hardy. SYNS. O. capense, 

 0. lucidum. 



O. lucidum (shining). A synonym of 0. japonieum. 



OPAQUE. Dull; the reverse of shining. In 

 botany, the term does not mean the reverse of 

 transparent. 



OPERA GIRLS. See Mantisia salta- 

 toria. 



OPERCULARIA (from operculum, a lid ; re- 

 ferring to the shape of the calyx). OKD. Rubiaceas. 

 A genus comprising fourteen species of Australian 

 greenhouse herbs or sub-shrubs, sometimes twining, 

 glabrous or hispid-pilose, often foetid. Flower- 

 heads white, small, terminal, or rising from the 

 forks of the branches, involucrate ; peduncles erect 

 or recurved. Leaves opposite, linear or oblong; 

 stipules connate with the petioles. The species 

 (of which two only are seen in cultivation) thrive 

 in a compost of sandy loam, a little fibry peat, 

 dried pieces of leaf mould, and a few pieces of 

 charcoal. Propagation may be effected by seeds, 

 sown in spring, on a mild hotbed ; by cuttings of 

 young shoots, several inches long ; or by division, 

 as growth commences. 



O. aspera (rough), fl. -heads globular, compound, on 

 short, recurved peduncles. June. I. shortly petiolate, 

 ovate or lanceolate, scabrous above, glabrous or pu- 

 bescent beneath, mostly Jin. to l^in. long, variable. 

 h. 1ft. 1790. Sub-shrub. SYN. O. oc 



O. hispida (hispid), fl.-heads on short, recurved pe- 

 duncles, smaller than in 0. aspera. July. I. petiolate, 

 ovate or lanceolate, either very hirsute and scarcely 

 scabrous, or very scabrous, mostly about iin. long. h. 

 1ft. 1790. Sub-shrub. 



O. ocymifolia (Basil-leaved). 

 pera. 



A synonym of 0. as- 



OPERCULATE. Covered with a lid. 

 OPHELIA. A synonym of Swertia (which 



OPHELUS. A synonym of Adansonia. 



O. 



Ophiocauloii continued. 



cissampeloides (Cissampelos-like). fl. , male ones numerous, 

 in stalked, terminal, and axillary, trichotomously divided, 

 many-flowered cymes. 1. orbicular or cordate, glaucous, markeit 

 with black dots beneath, deep green, often mottled with white 

 above, 2m. to 3m. long. Branches slender, cylindrical. West 

 tropical Africa, 1869. SY.X. Passiflora marmorata, of gardens. 



((jr. O. lo/l, O4.) 



OFHIODERMA. 



(which see). 



Included under Ophioglossum 



OPHIOGLOSSACEJE. A sub-order of Ferns, 

 characterised by the capsules being deeply two-valveil, 

 and opening down the side nearly to the base without 

 a ring. There are three genera Botrychium, Helmin- 

 thostachys, and Ophioglossum and about a score 

 species. 



FIG. 746. OPHIOGLOSSUM VULGATUM, showing Creeping Rhizor 

 Barren and Fertile Fronds. 



OPHIOCAULON (from ophis, a serpent, and Tcaulon, 

 a stem ; in reference to its climbing habit). ORP. 

 Passiflorew. A small genus (three or four species) of 

 stove, climbing, herbaceous, very glabrous shrubs, natives 

 of tropical Africa, Natal, and Madagascar. They are 

 allied to Modecca, but have a deeply five-parted calyx, 

 obscure corona, and sessile stigma. The undermentioned, 

 the only species in cultivation, thrives in well-drained 

 sandy loam and leaf mould, and does best when planted 

 out in a border inside the house, and its shoots trained 

 near the glass. Care must be taken to guard against 

 excess of moisture, particularly during the dull winter 

 months. For propagation, see Fassiflora. 



OPHIOGLOSSUM (from opliios, a snake, and glossa, 

 a tongue ; referring to the shape of the spike of fructifi- 

 cation). Adder's Tongue. Including Cheiroglossa and 

 Ophioderma. OBD. Filices. A small genus (about ten 

 species) of pretty, stove, greenhouse, or hardy Ferns. 

 Sporangia sessile, arranged in two rows, so as to form 

 a flattened spike, which forms a branch of the barren 

 frond, or is entirely distinct from it. About five species 

 have been introduced. For general culture, see Ferns. 

 O. bulbosum (bulbous). Rootstock tuberous, fronds 2in. to 4in. 

 long, the sterile division placed considerably below the middle, 

 iin. to lin. long, iin. broad, fertile spike Jin. to iin. long 

 peduncle IMn. to Zin. long when fully developed. North America, 

 &c. Half-hardy. 



