PEACH. By Bentham and Hooker the peach is included under the genus Prunus (Prunus persica), and its resemblance to the plum is indeed obvious; others have classed it with the almond, Amygdalus; while others again have considered it sufficiently distinct to constitute a genus of its own under the name Persia.
In general terms the peach may be said to be a medium sized tree, with lanceolate, stipulate leaves, borne on long, slender, relatively unbranched shoot, and with the flowers arranged singly, or in groups of two or more, at intervals along the shoots. The flowers have a hollow tube at the base bearing at its free edge five sepals, an equal number of petals, usually concave or spoon-shaped, pink or white, and a great number of stamens. The pistil consists of a single carpel with its ovary, style, stigma, and solitary ovule or twin ovules. This carpel is, in the first instance, free within the flower-tube, but, as growth goes on, the flower-tube and the carpel become fused together into one mass, the flesh of the peach, the inner layers of the carpel becoming woody to form the stone, while the ovule ripens into the kernel or seed. This is exactly the structure of the plum or apricot, and differs from that of the almond, which is identical in the first instance, only in the circumstance that the fleshy part of the latter eventually becomes dry and leathery and cracks open along a line called the suture.
The nectarine is a variation from the peach, mainly characterized by the circumstance that, while the skin of the ripe fruit is downy in the peach, it is shining and destitute of hairs in the nectarine. That there is no essential differences between the two is, however, shown but the facts that the seeds of the peach will produce nectarines, and vice versa, and that it is not very uncommon, though still exceptional, to see peaches and nectarines on the same branch, and fruits which combine in themselves the characteristics of both nectarines and peaches. The blossoms of the peach are found the autumn previous to their expansion, and this fact, together with the peculiarities of their form and position, requires to be borne in mind by the gardener in his pruning and training operations, as mentioned in HORTICULTURE (vol. xii. pp. 272, 273). The only point of practical interest requiring mention here is the very singular fact attested by all peach-growers, that, while certain peaches are liable to the attacks of a parasitic fungus known as mildew, others are not, showing a difference in constitution analogous to that observed in the case of human beings, some of whom will readily succumb to particular diseases, while others seem proof against their attacks. In the case of the peach this peculiarity is in some way connected with the presence of small glandular outgrowths on stalk, or at the base of the leaf. Some peaches have globular, others reniform glands, other none at all, and these latter trees are much more subject to mildew than are those provided with glands.
The history of the peach, almonds, and nectarine is interesting and important as regards the question of the origin of species and the production and perpetuation of varieties. As to the origin of the peach two views are held, that of Alphonse de Candolle, who attributes all cultivated varieties to a distinct species, probably of Chinese origin, and the adopted by many naturalists, but more especially by Darwin, who looks upon the peach as a modification of the almond. The importance of the subject demands that a summary of the principal facts and inferences bearing on this question should be given. In the first place, the peach as we now know it is has been nowhere recognized in the wild state. In the few instances where it is said to have been found wild the probabilities are the tree was an escape for cultivation. Aitchison, however, gathered in the Hazárdarakht ravine in Afghanistan a form with different-shaped fruit from that of the almond, being larger and flatter. " The surface of the fruit," he observes, "resembles that of the peach in texture and colour ; and nut is quite distinct from that of 419 [the wild almond]. The whole shrub resembles more what one might consider a wild form of the peach than that of the almond." It is admitted, however, by all competent botanists that the almond is wild in the hotter and drier parts of the Mediterranean an Levantine regions. Aitchison also mentions the almond as wild in some parts of Afghanistan, where it is known to the natives as "bédám." The same word that they apply to the cultivated almond. The branches of the tree are carried by the priests in religious ceremonies. It is not known as a wild plant in China or Japan.
As to the nectarine, of its origin as a variation form the peach there is abundant evidence, as has already been mentioned ; it is only requisite to add the very important fact that the seeds of the nectarine, even when that nectarine has been produced by budvariation from a peach, will generally produce nectarines, or, as gardeners say, " come true."
Darwin brings together the records of several cases, not only of gradations between peaches and nectarines, but also of intermediate forms between the peach and the almond. So far as we know, however, no case has yet been recorded of a peach or a nectarine producing an almond, or vice versa, although if all have had a common origin such an event might be expected. Thus the botanical evidence seems to indicate that the wild almond is the source of cultivated almonds, peaches, and nectarines, and consequently that the peach was introduced from Asia Minor or Persia, whence the name Persica given to the peach ; and Aitchisons discovery in Afghanistan of a form which reminded him of a wild peach lends additional force to this view.
On the other hand, Alphonse de Candolle, from philological and other considerations, considers the peach to be of Chinese origin. The peach has not, it is true, been found wild in China, but it has been cultivated there from immemorial ; it has entered into the literature and folk-lore of the people ; and it is designated by a distant name, " to " or " tao," a word found in the writings of Confusius five centuries before Christ, and even in other writings dating from the 10th century before the Christian era. Though now cultivated in India, and almost wild some parts of the north-west, and, as we have seen, probably also in Afganistan, it has no Sankrit name ; it is not mentioned in the Hebrew text of the Scriptures, nor in the earliest Greek times. Xenophon makes no mention of the peach of the peach, though the Ten Thousand must have traversed the country where, according to some, the peach is native, but Theophrastus, a hundred years later, does speak of it as Persian fruit, and De Candolle suggests that it might have been introduced into Greece by Alexander. According to his view, the seeds of the peach, cultivated for ages in China, might have been carried by the Chinese into Kashnir, Bokhara, and Persia between the period of the Sanskrit emigration and the Graeco-Persian period. Once established, its cultivation would readily extend westward, or, yon the other hand, by Cabul to north-western India, where its cultivation is not ancient. While the peach has been cultivated in China for thousands of years, the almond does not grow wild in that country, and its introduction I supposed not to go back farther than the Christian era.
On the whole, we should be inclined greater weight to the evidence from botanical than to that derived from philosophy, particularly since discovery both of the wild almond and of a form like a wild peach in Afghanistan. It may, however, well be that both peach and almond are derived from some pre-existing and now extinct from whose descendants have spread over the whole geographic area mentioned; but of course this is a mere speculation, though indirect evidence in its support might be obtained from the nectarine, of which no mention is made in ancient literature, and which, as we have seen, originates from the peach and reproduces itself by seed, thus offering the characteristics of a species in the act of developing itself. (M. T. M.)
The above article was written by: Maxwell T. Masters, M.D., F.R.S.; editor of Gardener's Chronicle; formerly Lecturer on Botany, St George's Hospital, London; author of Plant Life, Botany for Beginners, and numerous monographs in botanical works.