I have given a representation, in the last plate of the Picturesque Atlas of my American journey,[MA] of the dragon-tree of Orotava, taken from a drawing made in 1776 by F. d’Ozonne, and which I found among the posthumous papers of the celebrated Borda, in the still unprinted journal entrusted to me by the Dépôt de la Marine, and from which I have borrowed important astronomically-determined geographical, data besides many barometrical and trigonometrical notices.[MB] The measurement of the dragon-tree in the Villa Franqui was made in Borda’s first voyage with Pingré in 1771, and not in the second, made 1776 with Varela. It is asserted, that in the fifteenth century, during the early periods of the Norman and Spanish conquests, mass was performed at a small altar erected in the hollow trunk of this tree. Unfortunately, the Dracæna of Orotava lost one side of its leafy top in the storm of the 21st of July, 1819. There is a fine large English copper-plate engraving, which gives an exceedingly true representation of the present condition of the tree. The monumental character of these colossal living forms, and the impression of reverence which they have created among all nations, have led, in modern times, to a more careful study of the numerical determination of their age, and of the size of their trunks. The results of such investigations induced the elder Decandolle, (the author of the important treatise, entitled _De la Longévité des Arbres_,) Endlicher, Unger, and other distinguished botanists to conjecture, that the age of many existing vegetable forms may extend to the earliest historical times, if not to the records of the Nile, at least to those of Greece and Italy. In the _Bibliothèque Universelle de Genève_ (t. xlvii. 1831, p. 50) we find the following passage: “Numerous examples seem to confirm the idea, that there still exist, on our planet, trees of a prodigious antiquity—the witnesses, perhaps, of one or more of its latest physical revolutions. If we consider a tree as the combination of as many individual forms as there have been buds developed on its surface, one cannot be surprised if the aggregate resulting from the continual addition of new buds to the older ones, should not necessarily have any fixed termination to its existence.” In the same manner, Agardh says: “If in each solar year new parts be formed in the plant, and the older hardened ones be replaced by new parts capable of conducting sap, we have a type of growth limited by external causes alone.” He ascribes the short duration of the life of herbaceous plants, “to the preponderance of the production of blossoms and fruit over the formation of leaves.” Unfruitfulness in a plant insures a prolongation of its life. Endlicher adduces the instance of an individual plant of Medicago sativa, var. β versicolor, which lived eighty years because it bore no fruit.[MC]