[Illustration: Odontoglossum nebulosum.] PLATE I. ODONTOGLOSSUM NEBULOSUM, _Lindley_. CLOUDED ODONTOGLOSSUM. O. (LEUCOGLOSSUM, _Lindl._) pseudobulbis ovatis compressis 2-3-phyllis, foliis oblongis acutis basi conduplicatis pedunculo radicali erecto (apice) nutante 3-7-floro brevioribus, bracteis scariosis amplexicaulibus ovario duplo brevioribus, sepalis petalisque latioribus membranaceis oblongis undulatis apiculis recurvis, labelli ungue cucullato carnoso, lamellis duabus erectis dentibusque totidem anticis, limbo ovato acuto dentato subpubescente, columnâ apterâ elongatâ. (_Lindl. quibusdam mutatis_.) ODONTOGLOSSUM NEBULOSUM, _Lindl. Fol. Orch._ ODONTOGLOSSUM MAXILLARE, _Lemaire (nec Lindley), Illustration Horticole_ (1859), _t._ 200. Habitat in Mexico, prope Oaxaca (_Karwinski_, _Galeotti_, etc.), _circiter 5000 ft._ DESCRIPTION. PSEUDOBULBS _2 to 3 inches long, smooth, ovate, somewhat compressed, 2- or 3-leaved_. LEAVES _2 or 3 at the apex of the pseudobulbs, oblong, acute, shorter than the_ SCAPE, _which, rising from the base of the pseudobulbs, is bent down at its upper extremity by the weight of from 3 to 7 large and handsome_ FLOWERS. BRACTS _only half the length of the ovary, embracing the flower-stem_. SEPALS _1½ inches long_. PETALS _much wider than the sepals, and like them of an oblong form, waved at the margin, and a little recurved at the end, which is sharply pointed; both sepals and petals are of clear membranous white, clouded (as the name implies) by a profusion of spots or blotches of a reddish-brown colour, which extend to nearly half their length_. LIP _of the same texture and colour as the sepals, only that the brown blotches are broader, and that there is a patch of yellow on the claw; its upper portion is of an ovate form, acute, with the margins very much torn; its fleshy dish is hooded, or gathered into 2 erect plates, with a pair of teeth attached in front_. COLUMN _very long, destitute of wings_.