1112 



OAKESIA 



ODON TOGLOSSUM 



sessilifolia, Wats. Stem once forked: Ivs. oblong- 

 lanceolate, acute at each end ; margins minutely sca- 

 brous: capsule borne on a distinct stipe. Canada to Fla. 

 and Ark. B.M. 1402. L.B.C. 13:1262. G.W.F. 16. D. 51. 

 F. W. BARCLAY and W. M. 



OAT. Arena safira. 



OBELISCAKIA. See Lepacliys. 



1508. The wide-spreading Live Oak of the South. 

 (See Oak, page 1111.) 



6CHNA (old Greek name for a wild pear, which some 

 of these plants were thought to resemble in foliage). 

 Ochnacece. O. multiflora is a cool greenhouse shrub 

 cult, by a few fanciers for its remarkable appearance 

 when in fruit. The fls. are yellow, appear in spring, 

 and are borne to the number of 10-15 in racemes ter- 

 minating short lateral branches. The blossoms are 

 short-lived, but the calyx is persistent. Its 5 sepals are 

 greenish in flower, but become a bright red in fruit. The 

 receptacle increases until it becomes an inch or so thick, 

 globular and bright red. Upon it are borne black seed- 

 like bodies, which are the carpels. The red and black 

 make a fine contrast. This rare plant is best prop, by 

 cuttings struck in autumn. It is cult, in America, but 

 not advertised. 



Ochna is a genus of about 25 species of trees and 

 shrubs from tropical Asia and Africa: Ivs. deciduous, 

 alternate, minutely serrate, leathery, shining : fls. yel- 

 low, rarely greenish, jointed to the pedicels; sepals 5, 

 colored, imbricate, persistent ; petals 5-10 ; stamens 

 indefinite; anthers opening longitudinally or by pore- 

 like slits : ovary deeply 3-10-lobed ; lobes 1-celled, 

 1-ovuled; styles connate; drupes 3-10, sessile. 



multifldra, DC. Glabrous shrub, 4-5 ft. high: Ivs. 

 oblong-elliptical to oblanceolate-oblong: petals sessile: 

 anthers as long as the filaments, opening longitudinally: 

 sepals in fruit about 4 lines long. Upper Guinea. 



G. W. OLIVER and W. M. 



OcJma multiflora is a remarkably handsome shrub 

 for conservatory decoration. It is usually regarded as 

 a stove shrub, but has done well with us in a green- 

 house temperature of 55 (min.). It has a unique effect, 

 and to be properly appreciated specimens should stand 

 out. The drupelets are black, making a striking contrast 

 with the enlarged red receptacle, at a glance reminding 

 one of a spindle tree. In a good bottom heat, seeds ger- 

 minate in a month, and make neat little plants in a 

 year. We have not been so fortunate with cuttings. 

 Unfortunately for us, cat -birds appropriated all the 

 berries as soon as they became ripe. They entered 

 through the open spaces in the annex to our conserva- 

 tory- T. D. HATFIELD. 



6CIMUM. See Basil. 



OGOTILLO. Fouquieria splendens. 



ODONTADfiNIA (Greek, toothed glands). Apocy- 

 nacece. Here belongs the fine tropical yellow-fld. 

 climber sold as Dipladenia Harrisii, which rivals in 

 beauty the well known greenhouse Allamandas. The 

 fls. are fragrant, about 3 in. across, funnel-shaped, with 

 5 rounded, spreading lobes, and are more or less 

 streaked with red in the throat, at the base of the lobes, 

 and on the back of the tube. The treatment which George 



Mo William has given Dipladenias with such good results 

 (see Dipladenia, Vol. I) should be attempted for Odon- 

 tadenia, but O. speciosa perhaps grows at lower alti- 

 tudes, and may require the treatment usually given to 

 hothouse vines. All Odontadenias have yellow fls., 

 while Dipladenias are yellow only in the throat. 



Odoutadenia is a genus of about 8 species of tall, 

 shrubby, tropical American climbers : Ivs. opposite : 

 cymes loose, usually ample, rarely few-fld. and scarcely 

 branched : calyx 5-parted, the lobes remarkably blunt or 

 rounded; corolla-lobes twisted in the pointed bud, over- 

 lapping to the right and twisted to the left; stamens 

 fixed at the top of the narrow part of the tube. The 

 genus is distinguished from Dipladenia by the shape of 

 the calyx-lobes and by the cup-shaped group of toothed 

 glands below the pistil. 



speciosa, Benth. (Dipladenia Harrisii, Hook.). 

 Shrubby, branched climber: largest Ivs. 10-15 by 4-;~> 

 in., oblong, tapering, scarcely leathery, feather-veined, 

 often purplish beneath; petioles stout, scarcely 1 in. 

 long: racemes axillary and terminal; pedicels red, of ton 

 1 in. long, curved downwards : corolla-tube with a round- 

 ish base about % in. long and thick, then suddenly con- 

 stricted, then gradually widening into a funnel-shaped 

 fl. Brazil, Guiana, Trinidad. B.M. 4825. W- M 



ODONTOGLOSSUM (Greek, tooth-tongue; in allusion 

 to the crest on the labellum). Orchiddcece. A genus 

 of orchids embracing about 100 species, natives of the 

 higher regions of the Andes from Mexico and Guatemala 

 to Colombia and Bolivia. On account of their hand- 

 some flowers these plants are among the most favorite 

 orchids of cultivators. O. crispum is one of the finest of 

 all orchids. 



Plants epiphytic, with short rhizomes and 2-lvd. 

 pseudobulbs, often with sheathing leaves at the base: 

 fls. in few- tomany-fld. racemes or panicles arising from 

 the base of the pseudobulb; sepals and petals spread- 

 ing, free, or the lateral sepals rarely somewhat united 

 at the base; base of the labellum ascending parallel to 

 the column and sometimes adnate to the latter; lateral 

 lobes small, often erect; middle lobe large, spreading, 

 variously shaped ; column clavate, narrowed at the base, 

 longer than in Oncidium. 



This genus is closely related to Oncidium and Mil- 

 tonia, some of the species of the latter being generally 

 cultivated as Odontoglossums. These two genera are 

 easily distinguished from Odontoglossum by the label- 

 lum, which expands directly from the base of the col- 

 umn. There is perhaps no genus of orchids in which 

 the species are more variable and more closely related 

 than in Odontoglossum. Numerous varieties connect 

 the species by intermediate links, and the occurrence of 

 many natural hybrids makes the limitation of species in 

 this genus almost impossible. However much this may 

 add to the perplexity of the botanist, it gives the genus 

 an additional horticultural value and interest resulting 

 in the production of numerous garden hybrids and in 

 the selection of many varieties, one species, O. crispum, 

 having over a hundred named kinds. 



HEINRICH HASSELBRING. 



Odontoglossums follow the high western mountain 

 ranges from southern Mexico to southern Peru, and 

 usually grow at great altitudes. With few exceptions, 

 they are found in extremely moist situations where the 

 annual rainfall is excessive and the temperature more 

 or less even and cool throughout the year. 



The extreme heat of our summer interferes somewhat 

 with the culture of Odontoglossums in America, espe- 

 cially those of the O. crispum section, and it is neces- 

 sary to use every precaution during that season to 

 insure success. 



A lean-to or half -span roof structure of northern ex- 

 posure, protected by a brick or stone wall on the south 

 side, and with ample means of ventilation, is best suited 

 to Odontoglossum culture. Moreover, it should be pro- 

 vided with rolling shades elevated on framework 18 or 

 20 in. above the glass, to afford abundance of light, free 

 access of air and requisite shade, with the additional 

 assistance of keeping down the temperature in summer. 

 The interior is best fitted with solid beds, if possible, 

 but benches of stone flags or wood covered with ashes 

 or gravel an inch or two deep will answer very well. 



