Название: Origin of Cultivated Plants
Автор: Alphonse de Candolle
Издательство: Public Domain
Жанр: Зарубежная классика
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The seeds of the tea-plant often sow themselves beyond the limits of cultivation, thereby inspiring doubt among botanists as to the wild nature of plants encountered here and there. Thunberg believed the species to be wild in Japan, but Franchet and Savatier571 absolutely deny this. Fortune,572 who has so carefully examined the cultivation of tea in China, does not speak of the wild plant. Fontanier573 says that the tea-plant grows wild abundantly in Mantschuria. It is probable that it exists in the mountainous districts of South-eastern China, where naturalists have not yet penetrated. Loureiro says that it is found both “cultivated and uncultivated” in Cochin-China.574 What is more certain is, that English travellers gathered specimens in Upper Assam575 and in the province of Cachar.576 So that the tea-plant must be wild in the mountainous region which separates the plains of India from those of China, but the use of the leaves was not formerly known in India.
The cultivation of tea, now introduced into several colonies, has produced admirable results in Assam. Not only is the product of a superior quality to that of average Chinese teas, but the quantity obtained increases rapidly. In 1870, three million pounds of tea were produced in British India; in 1878, thirty-seven million pounds; and in 1880, a harvest of seventy million pounds was looked for.577 Tea will not bear frost, and suffers from drought. As I have elsewhere stated,578 the conditions which favour it are the opposite to those which suit the vine. On the other hand, it has been observed that tea flourishes in Azores, where good wine is made;579 but it is possible to cultivate in gardens, or on a small scale, many plants which will not be profitable on a large scale. The vine grows in China, yet the manufacture of wine is unimportant. Conversely, no wine-growing country grows tea for exportation. After China, Japan, and Assam, it is in Java, Ceylon, and Brazil that tea is most largely grown, where, certainly, the vine is little cultivated, or not at all; while the wines of dry regions, such as Australia and the Cape, are already known in the market.
Flax—Linum usitatissimum, Linnæus.
The question as to the origin of flax, or rather of the cultivated flax, is one of those which give rise to most interesting researches.
In order to understand the difficulties which it presents, we must first ascertain what nearly allied forms authors designate – sometimes as distinct species of the genus Linum, and sometimes as varieties of a single species.
The first important work on this subject was by Planchon, in 1848.580 He clearly showed the differences between Linum usitatissimum, L. humile, and L. angustifolium, which were little known. Afterwards Heer,581 when making profound researches into ancient cultivation, went again into the characters indicated, and by adding the study of two intermediate forms, as well as the comparison of a great number of specimens, he arrived at the conclusion that there was a single species, composed of several slightly different forms. I give a translation of his Latin summary of the characters, only adding a name for each distinct form, in accordance with the custom of botanical works.
Linum usitatissimum.
1. Annuum (annual). Root annual; stem single, upright; capsules 7 to 8 mm. long; seeds 4 to 6 mm., terminating in a point. α. Vulgare (common). Capsules 7 mm., not opening when ripe, and displaying glabrous partitions. German names, Schliesslein, Dreschlein. β. Humile (low). Capsules 8 mm., opening suddenly when ripe; the partitions hairy. Linum humile, Miller; L. crepitans, Böninghausen. German names, Klanglein, Springlein.
2. Hyemale (winter). Root annual or biennial; stems numerous, spreading at the base, and bent; capsules 7 mm., terminating in a point. Linum hyemale romanum. In German, Winterlein.
3. Ambiguum (doubtful). Root annual or perennial; stems numerous, leaves acuminate; capsules 7 mm., with partitions nearly free from hairs; seeds 4 mm., ending in a short point. Linum ambiguum, Jordan.
4. Angustifolium (narrow-leaved). Root annual or perennial; stems numerous, spreading at the base, and bent; capsules 6 mm., with hairy partitions; seeds 3 mm., slightly hooked at the top. Linum angustifolium.
It may be seen how easily one form passes into another. The quality of annual, biennial, or perennial, which Heer suspected to be uncertain, is vague, especially for the angustifolium; for Loret, who has observed this flax in the neighbourhood of Montpellier, says,582 “In very hot countries it is nearly always an annual, and this is the case in Sicily according to Gussone; with us it is annual, biennial, or perennial, according to the nature of the soil in which it grows; and this may be ascertained by observing it on the shore, notably at Maguelone. There it may be seen that along the borders of trodden paths it lasts longer than on the sand, where the sun soon dries up the roots and the acidity of the soil prevents the plant from enduring more than a year.”
When forms and physiological conditions pass from one into another, and are distinguished by characters which vary according to circumstances, we are led to consider the individuals as constituting a single species, although these forms and conditions possess a certain degree of heredity, and date perhaps from very early times. We are, however, forced to consider them separately in our researches into their origin. I shall first indicate in what country each variety has been discovered in a wild or half-wild state. I shall then speak of cultivation, and we shall see how far geographical and historical facts confirm the opinion of the unity of species.
The common annual flax has not yet been discovered, with absolute certainty, in a wild state. I possess several specimens of it from India, and Planchon saw others in the herbarium at Kew; but Anglo-Indian botanists do not admit that the plant is indigenous in British India. The recent flora of Sir Joseph Hooker speaks of it as a species cultivated principally for the oil extracted from the seeds; and Mr. C. B. Clarke, formerly director of the botanical gardens in Calcutta, writes to me that the specimens must have been cultivated, its cultivation being very common in winter in the north of India. Boissier583 mentions L. humile, with narrow leaves, which Kotschy gathered “near Schiraz in Persia, at the foot of the mountain called Sabst Buchom.” This is, perhaps, a spot far removed from cultivation; but I cannot give satisfactory information on this head. Hohenacker found L. usitatissimum “half wild” in the province of Talysch, to the south of the СКАЧАТЬ
570
Bretschneider,
571
Franchet and Savatier,
572
Fortune,
573
Fontanier,
574
Loureiro,
575
Griffith,
576
Anderson, quoted by Hooker.
577
578
Speech at the Bot. Cong. of London in 1866.
579
580
Planchon, in Hooker,
581
Heer,
582
Loret,
583
Boissier,