It proves to be a most variable species, and I am not surprised that my accomplished friend Professor Reichenbach should have considered the first examples sent to him from Clapton to differ so materially from those of _O. Alexandræ_, as described by myself, as to justify his regarding them as a distinct form, to which, in honour of Messrs. Low's very zealous collector, he gave the designation of _Bluntii_. Since then, however, so many intermediate varieties have made their appearance that it is clearly impossible to regard the two supposed species as really distinct. Specimens of the plant have been sent to me by Messrs. Low, Mr. W. W. Buller, Mr. Rucker, Mr. Day, and Mr. Paterson; it has also flowered at Knypersley, but as yet no two specimens have been alike for, while some were beautifully spotted on the lip and petals with brown or crimson, others, with the exception of the golden crest on the labellum, were of the purest white. To the last-named class belonged the specimens grown by Mr. Buller and Mr. Paterson, the latter of which were so eminently lovely that they will form the subject of a separate Plate. Mr. Blunt's name may very properly be associated with the spotted variety now figured, and which was taken from a plant that he sent to his employers at Clapton. _O. Alexandræ_ is nearly allied to _O. crispum_ and _O. Pescatorei_; but, independently of the structure of its flowers, differs from both in its invariably producing simple racemes instead of branched panicles. It flowers freely in the winter and spring months, and may apparently be cultivated with the greatest ease. Of course, coming as it does from a great elevation, it must not be kept too warm. DISSECTIONS.--1. Lip and column (_magnified_), seen in front. 2. Ditto, ditto, seen sideways. Plate XV [Illustration: Odontoglossum Reichenheimii.] PLATE XV. ODONTOGLOSSUM REICHENHEIMII. M. REICHENHEIM'S ODONTOGLOSSUM. O. (ISANTHIUM, _Lindl._) pseudobulbis oblongis aggregatis diphyllis vix sulcatis, foliis oblongo-lanceolatis acutis scapo maculato laxe paniculato 3-plo brevioribus, bracteis brevibus membranaceis, sepalis petalisque subæqualibus oblongo-lanceolatis apiculatis, labello oblongo basi cordato apice obtusato lobulato, callo tumido utrinque ante basin, carinâ geminâ in imâ basi. ODONTOGLOSSUM REICHENHEIMII, _Reichenbach fil. in Bonpl._ iii. 214; _idem in Pescatorea_, _sub t._ 19; _Walpers_, _Annales_, vi. _fasc._ 6. _Lemaire in Illustr. Hortic. pl._ 213. Habitat in MEXICO, _Ghiesbreght_. DESCRIPTION.