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ODONTOGLOSSUM_ ROSSILI zinaz 
(Ampliat. a Rchb. f.) (Leucoglossa aptera) 
vAR RUBESCENS LEUCOGLOSSUM. 
Pseudo-bulbis pyriformi-ovatis compressis monophyllis aggregatis, foliis a basi petiolato angustatis oblongis acutis, pedunculis gracilibus uni—sexfloris, 
bracteis triangulis acutis ovaria pedicellata longe non «quantibus, sepalis semilanceolato triangulis, tepalis cuneato oblongis acutis, hinc undulatis, multo majori- 
bus, labelli ungue cartilagineo, lineari canaliculato limbis anticis rotundatis supra processum ligulatum emarginatum insilientibus, lamina membranacea 
subcordato circulari usque trulliformi crispula, columna clavata gracili aptera. 
OponrTocLossuM Rossu, Lindl. Sert. Orch.,, sub t. 25!; Lindl. Bot. Reg. xxv., 1839, t. 28!; xxxi, 1845, pag. 52!; Lindl. Folia Orchidacea I., Odonto- 
glossum Nr. 20!; Maund. Bot. 5, 222, etc. 
ODONTOGLOSSUM ACUMINATUM, Hort. Lindl. lc, xxxi., pag. 52! 
ODONTOGLOssUM RossIt ACUMINATUM, Knw. Westc., Floral Cab,, iii, 1840, N. 129! 
ODONTOGLOssUM APTERUM, La Llav., Lex. Nov. Veg. Descr., Fasc. i., pag. 35 !; Rchb. £, Walp. Ann. vi., 833! Vix feliciter, Planta Llavei forsan 
numquam extricanda. 
“ODONTOGLOSSUM EHRENBERGII, Lk. KL, Otto Abb. 16 ;” Van Houtte Fl. Serres, viii., 846! 
Sepala viridia brunneo multimaculata. Tepala alba, basi brunneo maculata. Labelli unguis flavus intus rubro striolatus, plus minus velutinus, lamina alba. 
Columna alboviridula. 
VAR. RUBESCENS, Rchb, f,, Gard. Chron. 1879, Feb. 1, p. 138!: sepalis aquose ochraceis, raro roseolo suffusis rufo marmoratis, tepalis roseo omnino 
seu ex parte suffusis, plus minus brunneo maculatis, labelli lamina alba seu roscolo alba. 
ODONTOGLOSSUM RUBESCENS, Lindl. Journ. Hort. Soc. v., 35!; Lindl. Folia Orchidacea I. Odontoglossum Nr. 27!; Rchb, f. in Walp. Ann.,, vi., 834! 
J. Linden, Lucien Linden, et Emile Rodigas, Lindenia I, xxvi! 
ODONTOGLOssUM Rossi, Lindl. var. MAJUS, V. Houtte Flore des Serres, xx. 2110, pag. 95 (var. leucoglossa), 
Multae practerea varictates sunt descriptae, de quibus hic non dicendum. In Mexico praesertim occidentali in arboribus praccipue Quercubus Martio florens, 
Figurae analyticae offerunt callos varios, columnam antheriferam cum labello, column apicem sine anthera, pollinarium.—/. G. Rehdb. f. 
Tus charming Mexican Orchid belongs to that section of the genus which Lindley called Leucoglossum, on account 
of the prevalence of white labella in the species comprised in it. The group also contains such well known species as 
O. Cervantesii, nebulosum and Bictoniense, besides several others less common in cultivation. O. Rossii has affinity with 
O. stellatum on the one side and O. Dawsoni on the other. O. Rossii was discovered about fifty years ago by the collector 
whose name it bears. He found it near Oaxaca, the centre of the Mexican Orchid district, and sent plants to his employer, 
Mr. Barker, of Birmingham, who was the first to flower it in England. Of late years it has become very plentiful and may 
be seen growing by the hundred in many Orchid collections. It is without question one of the loveliest Orchids in 
cultivation and is valuable because it flowers in the depth of winter, and continues so long in bloom, while its simple 
culture gives it additional worth. The graceful sprays of flowers are well adapted for cutting, and for this purpose 
alone it is worth growing in large quantities. 
It is one of the most variable Orchids as regards the size of flowers. Between the small and the large forms, which 
have flowers measuring over three inches across, there is every intermediate size. The variation in colour is even more 
remarkable, it being difficult to find two alike. Usually the three sepals have a greenish ground, blotched and spotted with 
sepia brown; the petals are half white and the rest dark brown, while the lip is pure white surmounted by a yellow crest. 
These colours vary greatly in intensity. The column of the flower also varies in colour ; generally it is lilac, but sometimes 
white ; the crest too varies from orange yellow, through lemon yellow and white. There is no absolute line of distinction 
between Rossii pure and simple and the rubescens varieties, as the difference is merely a question of colour. If the 
flowers are over two inches across it is the rule to append the varietal name majus to the plant, but there is a considerable 
difference between the finest and the ordinary forms. The number of flowers on a spike varies according to the strength 
of the bulb. Usually there are two or three, but not often five, as shown in our plate, which represents a fine variety. 
Ifa few simple conditions are observed, there is no Orchid of easier culture than O. Rossii, although it has the 
reputation of being difficult to flower well. The reason of this may often be attributed to the practice of growing it like 
O. crispum, cool and moist all the year round. Being a Mexican plant it must have a decided resting period corresponding 
with the dry season in Mexico. During April and May the plants should be kept cool and dry. From midsummer 
through the winter until March, the plants must not be allowed to get dry, yet not over-watered. They should be kept 
in a light and airy place, and the temperature may rise to 70 deg. Fahr. in sun heat, and the night temperature may fall 
to 45 deg. or even slightly lower. An Odontoglossum house, or ordinary close and moist greenhouse, suits it well. 
Flowers are produced from the partially matured bulbs, which should be thoroughly ripened after having flowered, in order to 
ensure good flower spikes the next season. The plants may be either grown in suspended baskets or pans, or on wood 
blocks, with a little peat and moss round the roots. The soil should consist of three parts peat to one of sphagnum moss. 
Drawn by permission of His Grace the Duke of Marlborough from a plant in the Blenheim collection. 
