ODONTOGLOSSUM ROSEUM, _Lindl. in Bentham Plant. Hartweg_, p. 251. _Reichenbach fil. in Garden. Chron. April 20, 1867._ Habitat in PERU, _Backhouse_, Nuebrada de los Juntas, _Hartweg_. DESCRIPTION. PSEUDOBULBS _ovate, two-edged, much compressed, dark-coloured, from one to two inches long, carrying a short solitary oblong-lanceolate leaf_. LEAVES _very sharp-pointed linear-lanceolate, not half the length of the slender nodding graceful many-flowered_ RACEMES. BRACTS _ovate, slightly angular, much shorter than the_ PEDICELS. SEPALS _and_ PETALS _nearly equal, lanceolate, acuminate, linear, two-thirds of an inch long, of a beautiful bright rose colour_. LIP _about same length as the petals, pale whitish rose, three-lobed, bilamellate at the base, side-lobes rounded, very small, intermediate lobe sharp-pointed, obcuneate_. COLUMN _standing forward, rounded, provided at its apex with three membranous wings_. A charming little species long known by the specimens in the Lindleyan Herbarium. It was introduced--though in very limited quantities--by the Messrs. Backhouse several years ago, since which time it has always continued scarce. In Lindley's Herbarium the racemes are about the length of those represented in the figure, but in a specimen exhibited in 1872 by Mr. Linden the pseudobulbs, leaves, and racemes were nearly twice as large and as long as those in the Plate. The precise treatment that it affects has not yet been distinctly ascertained, but there can be no doubt that, being a denizen of high places on the mountain ranges in Peru, it prefers the coldest house. Plate 23 [Illustration: Odontoglossum triumphans.] PLATE XXIII. ODONTOGLOSSUM TRIUMPHANS. SPLENDID ODONTOGLOSSUM. O. (XANTHOGLOSSUM, _Lindl._) pseudobulbis ovatis 1-2-phyllis foliis lato lanceolatis acutis, basi attenuatis, racemo multifloro, bracteis triangularibus ovario pedicellato 4-5plo brevioribus, sepalis oblongo-acutis basi bene attenuatis, petalis subæqualibus latioribus, magis acuminatis, utrinque hinc illinc lobulatis, labello unguiculato basi bifalci, utrinque bicalloso laminâ panduratâ apiculatâ, columnæ alis rhombeis ascendentibus margine externo erosulis. ODONTOGLOSSUM TRIUMPHANS, _Reichenbach fil. Bonpl._ ii. 99; _Walpers Annales_, vi. p. 831; _Pescatorea_, _t._ 46. Habitat in N. GRENADA, _Warscewicz_. OCANA, 6000-8000 feet, _Schlim_, _Wagener_. DESCRIPTION.