ODONTOGLOSSUM VEXILLARIUM, _Rchb. fil. in Gard. Chron._ 1867, 901; _ibid._ 1872, p. 667, _cum Xylo_; 1873, p. 580, 644, _cum Xylo_, 885; _Hooker in Bot. Mag._ t. 6037; _Illustration Horticole_, 1873, Pl. cxiii. Habitat in N. GRENADA, _Bowman_, _Wallis_, _Roezl_, _Chesterton_. DESCRIPTION. PSEUDOBULBS _flattened, ovate-oblong, an inch or inch and a half long, bearing one or two keeled sharp-ended lanceolate_ LEAVES _from six inches to a foot long, by an inch or more wide, with a glaucous tint, especially on their upper surface_. SCAPES _slender, nodding, about the same length as the leaves, two to six-flowered, clasped at intervals by small triangular_ BRACTS. FLOWERS _flat, the largest in the genus, tinted more or less deeply with lovely rose_. SEPALS _and_ PETALS _somewhat variable in their relative forms, in most cases nearly the same size, oblong or obovate apiculate or obtuse, about an inch long, the former nearly white, the latter of the same hue as the lip_. LIP _generally of a rich rosy tint, expanding from a narrow sagittate claw into a round and ample, 2-lobed disk, more than double the size of the petals, with five dwarf calli and some yellow streaks at its base_. COLUMN _very short with rarely a trace of wings_. This is the handsomest of known _Odontoglossa_. In the year 1867 Mr. Low showed me a solitary flower, which had been sent to him by his collector (Bowman, I believe), but a discreet silence was observed as to the locality where the prodigy had been found, nor, alas, did living plants ever make their way to the Clapton Nursery. Subsequently the species was met with by Wallis--when collecting for Mr. Linden--and later still by Roezl; but although in each case a large number of specimens were packed up and despatched to Europe, they either died on the passage, or shortly after their arrival. Indeed, cultivators were almost beginning to despair, when, early in the spring of last year (1873), the arrival was announced of a small cargo of the beauteous novelty in most excellent condition at the establishment of Messrs. Veitch; to whom it had been forwarded by Mr. Henry Chesterton. Once safe in the Chelsea collection, it did not put the patience of Orchid-growers to any severe strain, for within little more than three months of its arrival vigorous flower-spikes were produced, and the plant itself exhibited--both in Regent's Park and at South Kensington--to the envy and admiration of all beholders. It seems to be very easy to manage, and produces its flower-scapes with the utmost profusion. Like all its congeners, it must be relegated to the cool Orchid-house, though probably it will be found to prefer the warmest end.