Nursery; and all these rival envoys, much to their own mortification and chagrin, found themselves sailing for the same destination in the same steamer on the same errand! It was now that the idea occurred to me of devoting a work of adequate dimensions to the illustration of the particular genus, which from the dried specimens in our herbaria, the plates in _Pescatorea_, the figures of Humboldt, and the descriptions of travellers was evidently destined to hold the first place among all the numerous company of cool Orchids; and thus began the present Monograph. I had expected that after the work of importation had fairly commenced, not only would the species described by Lindley and Reichenbach be easily obtained, but that along with these a multitude of others entirely new to science would likewise be received. In this respect, however, the results have scarcely come up to expectations; a circumstance that is partly to be accounted for by the difficulty attendant on their importation,[2] but which is owing, I grieve to say, in a far greater degree to the untimely deaths of those zealous collectors, Bowman and Pearse, who, when in the very heart of the cool Orchid regions of Ecuador and Peru, succumbed under the pressure of their arduous labours. In Mexico, from which much novelty was expected, little has been added to the number of _Odontoglossa_ previously known, and the same may be said of Costa Rica, notwithstanding the vigorous exertions of Mr. Endries. But in these countries it is evident that the genus is not so fully developed as in the mountain ranges of New Grenada, Quito, and Peru. From the latter country little indeed has yet been received, although the eastern slopes of its Andean chain are probably richer in species of unknown or unimported Orchids than any other portion of the globe. But we must await further improvements in the navigation of the affluents of the mighty Amazon, before we can hope to receive any large instalment of these much-coveted treasures. A combination of the various causes referred to above, by limiting the choice of materials, has seriously delayed the publication of this work, which I had hoped would by this time have reckoned at least a dozen parts. But as there seems to be no immediate prospect of these hindrances to more rapid progress being taken out of the way, and as the sands of my life are fast running out, I have thought it best in the interests of my subscribers, to make the present number the last. The six parts now published will, however, form a volume of convenient size, and one which may, as I trust, serve to show how rich New Grenada is in the members of this glorious genus. What wealth of _Odontoglossa_ Peru may possess, I must leave some future botanist to unfold. He will have a pleasant task, and will probably have doubled the roll of the genus as now known, before his work is done.