PSEUDOBULBS _rather long and narrow, compressed, about 3 inches in length_. LEAVES, _one on each pseudobulb, less than a span long, membranous, sharp-pointed, narrowed at the base into a channelled petiole_. BRACTS _about an inch long, scariose, very acuminate_. SCAPE _longer than the leaves, only partially covered by the bracts, bearing from 2 to half-a-dozen flowers of a very delicate texture, and of snowy whiteness with the exception of the yellow crest on the lip and a few brown blotches on the lower half of the sepals and (though in a less degree) of the petals also_. SEPALS _rather narrow, oblong, acute_. PETALS _broader than the sepals and waved at the margin_. LIP _with a heart-shaped crenulate plate (occasionally suffused with a rosy tint), and a yellow 3-lobed callus at its base, the front portion of which is longer than the lateral ones (which are turned inwards from the base upwards), and split into two divergent members_. COLUMN _slender, clavate, wingless_. This pretty species was first described by Professor Reichenbach, from materials derived from the collection of Mr. Warner, of Broomfield, in compliment to whom he named it. It also flowered with the late Mr. Cauty, of Liverpool, who kindly sent me the specimens from which the figure was prepared, but these were smaller and less rich in their colouring than those of Mr. Warner. We have no precise information as to the locality where _O. Warnerianum_ grows wild, but there can be no doubt that it comes from some part of Mexico, whence we have other species, _e.g._ _O. Rossii_, _O. Ehrenbergii_, and _O. nebulosum_, to all of which it is nearly allied. It flowers in the later autumn and winter months, but like most of the other members of its section (_Leucoglossum_), is of a delicate habit, and requires to be very carefully handled. It seems to prefer a moderate heat and perhaps a slightly drier atmosphere than that in which the New Granada and Peruvian Odontoglossa evidently delight; the compost or materials in which the roots grow, should on no account be allowed to become sodden. DISSECTIONS.--1. Lip and column (_magnified_), seen in front; 2. Ditto, seen sideways. PLATE XIII. FIG. 2. ODONTOGLOSSUM STELLATUM. STELLATE ODONTOGLOSSUM. O. (LEUCOGLOSSUM, _Lindl._) pseudobulbis ovalibus compressis, foliis solitariis lanceolatis recurvis, scapis erectis 1-2-floris brevioribus, bracteis ovarii triquetri medium non attingentibus, sepalis petalisque æqualibus linearibus acuminatis herbaceis, labello rhomboideo subrotundo grosse dentato appendice unguis truncatâ quadridentatâ apice liberâ. ODONTOGLOSSUM STELLATUM, _Lindl. in Bot. Reg._ 1841, _Misc._ 25; _Fol. Orch._ _n._ 18. ODONTOGLOSSUM EROSUM, _Reichenbach fil. Bonpl._ ii. 99; _A. Rich. Gal. in Ann. Sc. Nat._ Jan. 1845. Habitat in GUATEMALA, _Skinner_; MEXICO, _Hartweg_; VERAGUAS, _Warszewicz_. DESCRIPTION.