Epiphytal. _Stems_ forming a very short woody annulated rootstock (ebulbous), from which are protruded the thick greenish roots. _Leaves_ elliptic-oblong acute, leathery, slightly keeled, somewhat recurved at the point, a foot to a foot and a half in length, dull deep green speckled with purple, the speckling most strongly marked on the under surface and on the younger parts. _Panicles_ rigid, short-branched, on green peduncles, which spring from the base of the leaf, and are blotched with purple, and invested with scarious ovate-acuminate bracts, the lower ones being larger and much lengthened out. _Flowers_ showy, fragrant like vanilla; _sepals_ oblong-obovate, narrowed below, concave, keeled, wavy at the edge, yellowish green externally, internally brighter yellow-green and spotted irregularly with reddish brown, a broad blotch of brown occupying the base; _petals_ similar to the sepals in size, form, and colour; _lip_ one and a half inch long, three-lobed, lateral or basal lobes magenta-purple, darkest at the centre, triangular-oblong, with three crests diminishing upwards on the disk between them; the middle or anterior lobe clawed, transversely-oblong, emarginate, the anterior half of the claw and the broad anterior lobe itself whiter. _Column_ short, white, with a pair of magenta-coloured oblique oblong side wings, and a red anther cap. Oncidium Lanceanum Louvrexianum, _Reichenbach fil._, in _Gardeners’ Chronicle_, N.S., xvii., 218. We now present to our subscribers the figure of a most beautiful Orchid which belongs to an extensive genus, the species of which vary much in their growth, bulbs, foliage, and flowers, the latter including almost every gradation of size and many shades of colour. The Oncidiums are among the most useful of plants for decorative purposes, as every one must know who grows Orchids. _Oncidium Lanceanum_ is quite distinct as a species from any others with which we are acquainted and is remarkable for having a rich rosy violet lip; the typical form we hope to be able to figure at some future time. The variety _Louvrexianum_, as will be seen from the annexed illustration, differs from the type in having the lip white. Our plate was prepared from an excellent drawing of a plant which flowered in the fine collection of orchids belonging to Mons. D. Massange de Louvrex, of Marche, in Belgium—one of the best collections in that country, and one also in which the plants are well cultivated, and many unique specimens are to be seen.