Odontoglossum 



( 125) 



Odontoglossum 



supports. These lath blinds are useful also in 

 another way, for, if lowered at night during severe 

 weather, they afford some amount of shelter, and 

 thus reduce the need of fire heat which the grower 

 of cool Orchids considers a necessary evil. Canvas 

 or mats hung round the glass sides of the house 

 assist materially in the same direction. Such 

 protection must be removed at dawn. Odonto- 

 glossums love shelter from bright sunshine, but, 

 this granted, they love plenty of light. Heavily 

 shaded plants do not show that bronzy purple hue 

 on their fully developed leaves and pseudo-bulbs, 

 which is the surest evidence of rude health. 



Various Potting Materials. The Bracken 

 rhizomes, found so plentifully in peat, are, when 

 cut small, taking the place of crocks in the potting 

 of Odontoglossums, and with good results. Polypody 

 fibre, the matted roots of Polypodiuin vulgare, was 

 at one time suggested as a good substitute for, and 

 an improvement upon, peat, but it has proved 

 neither the one nor the other in this country. 

 Quite recently leaf mould has been put forward as 

 an ideal material in which to pot Odontoglossums, 

 and many other Orchids. In Belgium and France 

 it is extensively used, and with the best possible 

 results, but the terre brut/ere of the Continental 

 growers must not be confounded with the ordinary 

 leaf mould so widely used by British plantsmen ; it- 

 is rather to be compared with the elastic, spongy 

 material that forms the floor of old Beech and Oak 

 woods. This is cheap and also saves labour, as but 

 few crocks are needed for drainage, and the larger 

 bulk of vegetable matter used keeps the Odonto- 

 glossum roots moist, with less watering. In potting 

 with leaf mould, the bases of the pseudo-bulbs 

 should be -J" below the pot rim, this allowing room 

 for a surfacing of live sphagnum. 



Some Special Points. A few species require a 

 distinct season of rest. Thus the group consisting 

 of grande, Insleayi, schlieperianmn, williamsianum, 

 and their varieties, should only be grown in the 

 cool-house during summer. Remove them to a 

 Cattleya house early in the autumn, or, better still, 

 treat them as intermediate house Orchids all the 

 year round, and as soon as flowering is over, and 

 the new bulbs have finished growth, gradually 

 withhold water, giving hardly any during winter 

 and spring. About Mayor June, when new growths 

 and new roots appear, pot or top-dress as neces- 

 sary, and water sparingly. Flower spikes appear 

 at the base of new bulbs. Another species requiring 

 similar treatment is the fragrant, pendulous-spiked 

 citrosmum, which should be grown in pans and 

 ba.-kets suspended in the Cattleya (or similar) 

 house. From the time growth is completed until the 

 new growth and flower spike have simultaneously 

 appeared, it should have only sufficient water to 

 keep the pseudo-bulbs from shrivelling. Repot 

 immediately after flowering. Such species as 

 coronarium and londesboroughianum are rambling 

 growers, and are best cultivated on a long raft or 

 in a basket, suspended in an intermediate house. 

 A few species, notably harryanum, Krameri, 

 madrense, and Oerstedii, do best in a little higher 

 temperature than the cool-house affords, as also do 

 the hybrids having one of these as a parent. If the 

 cool-house is part of a range of glass, it usually is 

 warmer at one end than the other, and a careful 

 observer will soon find that cirrhosum, Hallii, 

 pardinum, etc., appreciate the warmer positions. 



Diseases and Pests. Of the former, those known 

 technically as " spot " and " brown tip " (or yellow 

 tip) come more properly under the heading of 



complaints than diseases ; the former is the result 

 of excessive moisture, sodden compost, and the like, 

 while the latter appears to be caused by too low a 

 temperature. There are numerous pests, tiny slugs 

 and snails being among the worst. These are best 

 caught at night by the aid o a lantern, or they 

 may be trapped in Lettuce leaves, etc. Protect 

 young spikes by a ring of cotton wool. Thrips 

 will appear if a moist atmosphere is not main- 

 tained ; sponging, and dusting with tobacco 

 powder, are remedies. Light fumigation, or 

 vaporising, at regular intervals, will answer for 

 green fly, removing flowering plants during the 

 operation. 



Principal Species and Varieties : 

 [NOTE. The Kew authorities have been followed 

 in compiling the lists of Odontoglossums.] 



Alexandra; (see crispum). (fine reddish pur. 



apterum, 10" to 15", My., blotches), mundyauum, 



wh., spotted reddish nobilius, Oakfield Suu- 



br. (syii. uebulosum). rise, pittianum, Prince 



Two very distinct vars. of Wales, Princess 



are caudidulum, spot- Christian, purpuras- 



less ; and pardiuum, ceils, Queen Victoria, 



richly spotted. Rex, roseuin guttatum, 



Bluntii (see crispum). Sanderte (huge crim. 



Cervautesii, 6", spr.,wh. blotches), sanderianum, 

 or blush, with br. bars sehroderianum, Sera- 

 iii concentric rings ; phini (pure wh.), Star- 

 decorum and majus are light, Stevensii (fine 

 fine forms. form, marked reddish 



cirrhosum, 1' to 3', spr., br.), The Earl, Triauas, 



wh., spotted pur. ; veitchianum, Victoria 



hrubyanum is a faintly Regina, virginale, 



marked and klabo- "Warneri, Wolsten- 



chorum a richly spotted holmite, and xanthotes 



var. (yel). 



citrosmuin, 8", My., wh. Edwardi, 2i' to 4 , spr., 



or pk., lip ro., yel.; deep pur., yel. callus on 



spikes depending H' to lip, fragrant; a strong 



3' ; flowers very fra- grower, with Ivs. some- 



grant ; the vars. album, 

 roseum.and sulphureum 

 are pretty colour varia- 

 tions. 



coronarium, 1' to H', spr., 

 glossy reddish br. , 

 marked yel. 



miniatum, denser habit, 

 smaller and brighter. 



crispum, 1' to 2J', spr., a 

 most variable species, 

 may be wh., ro., or 

 even yel. tinted ; rarely 

 unspotted; usually spot- 

 ted or blotched, with 

 ro., crim,, pur., br., 

 chocolate red, or reddish 

 pur. (s-y;/.s-. Alexandras 

 and Bluntii). A few 

 of the finest and most 

 distinct vars. are apia- 

 tum (flowers over 4" 

 broad), ashworthiauum, 

 augustum, aureum (suf- 

 fused ]>ale yel., < /'. 

 123) Baroness Schroder, 

 Cooksouii, delleuse (br. , 

 yel.), Duke of York, 

 Franz Masereel(gramlly 



times 2V long. 



gloriosum, 2', spr., yel., 

 marked br. , fragrant, 

 spidery form. 



grande, 8" to 12", aut., 

 yel. , shining reddish 

 br., large, showy 

 flowers, three to six 

 on scape; magniricum, 

 ]>ittianum,and Sandera; 

 are good forms. 



Hallii, iy to 4', spr., 

 variable, generally yel., 

 chocolate red, lip yel. 

 There are numerous 

 beautiful forms, such 

 as Edward VII., leuco- 

 glossum (wh. lip), inag- 

 nificum, and xantho- 

 glossum (deep yel. lip). 



harryanum, \\' to 2i', 

 Ap., ,Te., sepals chest- 

 nut br., yel., petals 

 yel., wh., pur., br., lip 

 wh., pur., yel. ; the 

 chief vars. are flaves- 

 cens, Haywood's, and 

 wilsonianum. 



hastilabium,2 { 'to 5', sum. , 



blotched blood red, yel., grn., spotted pur., 



crim.), Golden Queen br., lip wh., pur. 

 (yel.), heliotropium Kegeljani, li' to 2J', spr., 



(speckled br. on 

 ground), LelmiNimii 

 (spike nearly always 

 branched), Luciaui 



pale yel., marked br. ; 

 broad, rounded flowers 

 (.-nit. polyxanthum) : 

 Gatton Park var. and 



