PSEUDOBULBS _ovate, somewhat compressed, about an inch long, bearing 1 (rarely 2) narrow lanceolate_ LEAVES _of about the same length as the slender nodding many-flowered_ RACEMES. _The_ FLOWERS, _of which there are from six to twelve (or more) crowded together on the racemes, are all expanded at the same time, and emit a pleasant honey-like smell_. SEPALS _and_ PETALS _nearly equal, less than an inch long, lanceolate, acuminate, of a creamy white sprinkled over with numerous crimson dots_. LIP _about the same length as the sepals, and of the same hue, but destitute of spots except at the apex, the central portion bearing a large crimson mark nearly in the form of the letter_ W; _the lip's base is formed of two parallel blunt lamellæ out of which springs the main limb which is broadly ovate, curled and jagged at the edges and recurved and acuminate at its extremity; at the point of junction with the unguis or claw occur two horned falcate processes, between which a small tumour is interposed, at foot of which are two short and blunt horns_. COLUMN _short, bifid, angular with three or four straggling cirrhi or filaments on either side_. This pretty little _Odontoglossum_ comes from Ocaña, where it was first discovered by Mr. Low's collector many years ago. At that time none of the plants reached England alive, but some dried specimens that found their way to Professor Reichenbach, enabled the great German Orchidist to name and describe the species; which turns out to be nearly allied to _O. nævium_. It has been met with by M. Roezl and other collectors, but is still a rare plant, as its constitution is apt to succumb under a long journey by sea and land. The specimens from which Mr. Fitch prepared his drawing, flowered in the spring of 1871, in the collection of the Royal Horticultural Society;--the plants having been purchased at one of Stevens' sales, among a "miscellaneous lot" of doubtful things. The species is a free-flowerer, and sends out an agreeable honey-like odour, but in point of beauty is scarcely a rival for _O. nævium_. It seems to require rather more heat than the latter species, which is one of the coolest of cool Orchids. Plate XXIX [Illustration: Odontoglossum vexillarium.] PLATE XXIX. ODONTOGLOSSUM VEXILLARIUM. BROAD-LIPPED ODONTOGLOSSUM. O. (PHALÆNOPSIDEA) pseudobulbis ovato-oblongis compressis 1-2-phyllis; foliis pedalibus subglaucescentibus carinatis lanceolatis acutis pedunculis gracilibus 2-6-floris subæqualibus; bracteis triangulis minutis; floribus maximis roseo suffusis; sepalis oblongo-ligulatis apiculatis; petalis conformibus vel paulò latioribus subacutis vel obtusis; labello maximio flabellato orbiculari bilobo, in unguem brevem hastatum contracto, carinis quinis abruptis in basi; columnâ brevissimâ exalatâ.