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PART III.
Summary and Conclusion

CHAPTER I.
GENERAL TABLE OF SPECIES, WITH THEIR ORIGIN AND THE EPOCH OF THEIR EARLIEST CULTIVATION

The following table includes a few species of which a detailed account has not been given, because their origin is well known, and they are of little importance.

Explanation of the signs used in the table: (1) annual, (2) biennial, perennial, small shrub, shrub, small tree, tree. The letters indicate the certain or probable date of earliest cultivation. For the species of the old world: A, a species cultivated for more than four thousand years (according to ancient historians, the monuments of ancient Egypt, Chinese works, and botanical and philological indications); B, cultivated for more than two thousand years (indicated in Theophrastus, found among lacustrine remains, or presenting various signs, such as possessing Hebrew or Sanskrit names); C, cultivated for less than two thousand years (mentioned by Dioscorides and not by Theophrastus, seen in the frescoes at Pompeii, introduced at a known date, etc.). For American species: D, cultivation very ancient in America (from its wide area and number of varieties); E, species cultivated before the discovery of America, without showing signs of a great antiquity of culture; F, species only cultivated since the discovery of America.

GENERAL TABLE OF SPECIES

Примечание 1²¹⁷⁷

Common Haricot– Phaseolus vulgaris (1).

Musk Gourd– Cucurbita moschata (1).

Fig-leaved Gourd– Cucurbita ficifolia,

CHAPTER II.
GENERAL OBSERVATIONS AND CONCLUSIONS

Article I.—Regions where Cultivated Plants originated

In the beginning of the nineteenth century, the origin of most of our cultivated species was unknown. Linnæus made no efforts to discover it, and subsequent authors merely copied the vague or erroneous expressions by which he indicated their habitations. Alexander von Humboldt expressed the true state of the science in 1807, when he said, “The origin, the first home of the plants most useful to man, and which have accompanied him from the remotest epochs, is a secret as impenetrable as the dwelling of all our domestic animals… We do not know what region produced spontaneously wheat, barley, oats, and rye. The plants which constitute the natural riches of all the inhabitants of the tropics, the banana, the papaw, the manioc, and maize, have never been found in a wild state. The potato presents the same phenomenon.”²¹⁷⁸

At the present day, if a few cultivated species have not yet been seen in a wild state, this is not the case with the immense majority. We know at least, most frequently, from what country they first came. This was already the result of my work of 1855, which modern more extensive research has confirmed in almost all points. This research has been applied to 247 species,²¹⁷⁹ cultivated on a large scale by agriculturists, or in kitchen gardens and orchards. I might have added a few rarely cultivated or but little known, or of which the cultivation has been abandoned; but the statistical results would be essentially the same.

Out of the 247 species which I have studied, the old world has furnished 199, America 45, and three are still uncertain.

No species was common to the tropical and austral regions of the two hemispheres before cultivation. Allium schœnoprasum, the hop (Humulus lupulus), the strawberry (Fragaria visca), the currant (Ribes rubrum), the chestnut (Castanea vulgaris), and the mushroom (Agaricus campestris), were common to the northern regions of the old and new worlds. I have reckoned them among the species of the old world, since their principal habitation is there, and there they were first cultivated.

A great number of species originated at once in Europe and Western Asia, in Europe and Siberia, in the Mediterranean basin and Western Asia, in India and the Asiatic archipelago, in the West Indies and Mexico, in these two regions and Columbia, in Peru and Brazil, or in Peru and Columbia, etc., etc. They may be counted in the table. This is a proof of the impossibility of subdividing the continents and of classing the islands in well-defined natural regions. Whatever be the method of division, there will always be species common to two, three, four, or more regions, and others confined to a small portion of a single country. The same facts may be observed in the case of uncultivated species.

A noteworthy fact is the absence in some countries of indigenous cultivated plants. For instance, we have none from the Arctic or Antarctic regions, where, it is true, the floras consist of but few species. The United States, in spite of their vast territory, which will soon support hundreds of millions of inhabitants, only yields, as nutritious plants worth cultivating, the Jerusalem artichoke and the gourds. Zizana aquatica, which the natives gathered wild, is a grass too inferior to our cereals and to rice to make it worth the trouble of planting it. They had a few bulbs and edible berries, but they have not tried to cultivate them, having early received the maize, which was worth far more.

Patagonia and the Cape have not furnished a single species. Australia and New Zealand have furnished one tree, Eucalyptus globulus, and a vegetable, not very nutritious, the Tetragonia. Their floras were entirely wanting in graminæ similar to the cereals, in leguminous plants with edible seeds, in Cruciferæ with fleshy roots.²¹⁸⁰ In the moist tropical region of Australia, rice and Alocasia macrorhiza have been found wild, or perhaps naturalized, but the greater part of the country suffers too much from drought to allow these species to become widely diffused.

In general, the austral regions had very few annuals, and among their restricted number none offered evident advantages. Now annual species are the easiest to cultivate. They have played a great part in the ancient agriculture of other countries.

In short, the original distribution of cultivated species was very unequal. It had no proportion with the needs of man or the extent of territory.

Article II.—Number and Nature of Cultivated Species at Different Epochs

The species marked A in the table on pp. 437-446 must be regarded as of very ancient cultivation. They are forty-four in number. Some of the species marked B are probably as ancient, though it is impossible to prove it. The five American species marked D are probably cultivated as early as those in the category C, or the most ancient in the category B.

As might be supposed, the species A are especially plants provided with roots, seeds, and fruits proper for the food of man. Afterwards come a few species having fruits agreeable to the taste, or textile, tinctorial, oil-producing plants, or yielding stimulating drinks by infusion or fermentation. There are among these only two green vegetables, and no fodder. The orders which predominate are the Cruciferæ, Leguminosæ, and Graminaceæ.

The number of annuals is twenty-two out of the forty-four, or fifty per cent. Out of five American species marked D, two are annuals. In the category A, there are two biennials, and D has none. Among all the Phanerogams the annuals are not more than fifty per cent., and the biennials one or at most two per cent. It is clear that at the beginning of civilization plants which yield an immediate return are most prized. They offer, moreover, this advantage, that their cultivation is easily diffused or increased, either because of the abundance of seed, or the same species may be grown in summer in the north, and in winter or all the year round in the tropics.

Herbaceous perennial plants are rare in categories A and D. They are only from two to four per cent., unless we include Brassica oleracea, and the variety of flax which is usually perennial (L. angustifolium), cultivated by the Swiss lake-dwellers. In nature herbaceous perennials constitute about forty per cent. of the Phanerogams.²¹⁸¹

A and D include twenty ligneous species out of forty-nine, that is about forty-one per cent. They are in the proportion of forty-three per cent. of the Phanerogams.

Thus the earliest husbandmen employed chiefly annuals or biennials, rather fewer woody species, and far fewer herbaceous perennials. These differences are due to the relative facility of cultivation, and the proportion of the evidently useful species in each division.

The species of the old world marked B have been in cultivation for more than two thousand years, but perhaps some of them belong to category A. The American species marked E were cultivated before the discoveries of Columbus, perhaps for more than two thousand years. Many other species marked (?) in the table date probably from an ancient epoch, but as they chiefly exist in countries without a literature and without archæological records we do not know their history. It is useless to insist upon such doubtful categories; on the other hand, the plants which we know to have been first cultivated in the old world less than two thousand years ago, and in America since its discovery, may be compared with plants of ancient cultivation.

These species of modern cultivation number sixty-one in the old world, marked C, and six in America, marked F; sixty-seven in all.

Classed according to their duration, they number thirty-seven per cent. annuals, seven to eight per cent. biennials, thirty-three per cent. herbaceous perennials, and twenty-two to twenty-three per cent. woody species.

The proportion of annuals or biennials is also here larger than in the whole number of plants, but it is not so large as among species of very ancient cultivation. The proportions of perennials and woody species are less than in the whole vegetable kingdom, but they are higher than among the species A, of very ancient cultivation.

The plants cultivated for less than two thousand years are chiefly artificial fodders, which the ancients scarcely knew; then bulbs, vegetables, medicinal plants (Cinchonas); plants with edible fruits, or nutritious seeds (buckwheats) or aromatic seeds (coffee).

Men have not discovered and cultivated within the last two thousand years a single species which can rival maize, rice, the sweet potato, the potato, the bread-fruit, the date, cereals, millets, sorghums, the banana, soy. These date from three, four, or five thousand years, perhaps even in some cases six thousand years. The species first cultivated during the Græco-Roman civilization and later nearly all answer to more varied or more refined needs. A great dispersion of the ancient species from one country to another took place, and at the same time a selection of the best varieties developed in each species. The introductions within the last two thousand years took place in a very irregular and intermittent manner. I cannot quote a single species cultivated for the first time after that date by the Chinese, the great cultivators of ancient times. The peoples of Southern and Western Asia innovated in a certain degree by cultivating the buckwheats, several cucurbitaceæ, a few alliums, etc. In Europe, the Romans and several peoples in the Middle Ages introduced the cultivation of a few vegetables and fruits, and that of several fodders. In Africa a few species were then first cultivated separately. After the voyages of Vasco di Gama and of Columbus a rapid diffusion took place of the species already cultivated in either hemisphere. These transports continued during three centuries without any introduction of new species into cultivation. In the two or three hundred years which preceded the discovery of America, and the two hundred which followed, the number of cultivated species remained almost stationary. The American strawberries, Diospyros virginiana, sea-kale, and Tetragonia expansa introduced in the eighteenth century, have but little importance. We must come to the middle of the present century to find new cultures of any value from the utilitarian point of view, such as Eucalyptus globulus of Australia and the Cinchonas of South America.

The mode of introduction of the latter species shows the great change which has taken place in the means of transport. Previously the cultivation of a plant began in the country where it existed, whereas the Australian Eucalyptus was first planted and sown in Algeria, and the Cinchonas of America in the south of Asia. Up to our own day botanical or private gardens had only diffused species already cultivated somewhere; now they introduce absolutely new cultures. The royal garden at Kew is distinguished in this respect, and other botanical gardens and acclimatization societies in England and elsewhere are making similar attempts. It is probable that tropical countries will greatly profit by this in the course of a century. Others will also find their advantage from the growing facility in the transport of commodities.

When a species has been once cultivated, it is rarely, perhaps never completely, abandoned. It continues to be here and there cultivated in backward countries, or those whose climate is especially favourable. I have passed over some of these species which are nearly abandoned, such as dyer’s woad (Isatis tinctoria), mallow (Malva sylvestris), a vegetable used by the Romans, and certain medicinal plants formerly much used, such as fennel, cummin, etc., but it is certain that they are still grown in some places.

The competition of species causes the cultivation of some to diminish, of others to increase; besides, vegetable dyes and medicinal plants are rivalled by the discoveries of chemists. Woad, madder, indigo, mint, and several simples must give way before the invasion of chemical products. It is possible that men may succeed in making oil, sugar, and flour, as honey, butter, and jellies are already made, without employing organic substances. Nothing, for instance, would more completely change agricultural conditions than the manufacture of flour from its known inorganic elements. In the actual state of science, there are still products which will be more and more required of the vegetable kingdom; these are textile substances, tan, indiarubber, gutta-percha, and certain spices. As the forests where these are found are gradually destroyed, and these substances are at the same time more in demand, there will be the greater inducement to cultivate certain species.

These usually belong to tropical countries. It is in these regions also, particularly in South America, that fruit trees will be more cultivated – those of the order Anonaceæ for instance, of which the natives and botanists already recognize the value. Probably the number of plants suitable for fodder, and of forest trees which can live in hot dry countries, will be increased. The additions will not be numerous in temperate climates, nor especially in cold regions.

From these data and reflections it is probable that at the end of the nineteenth century men will cultivate on a large scale and for use about three hundred species. This is a small proportion of the one hundred and twenty or one hundred and forty thousand in the vegetable kingdom; but in the animal world the proportion of creatures subject to the will of man is far smaller. There are not perhaps more than two hundred species of domestic animals – that is, reared for our use, – and the animal kingdom reckons millions of species. In the great class of molluscs the oyster alone is cultivated, and in that of the Articulata, which counts ten times more species than the vegetable kingdom, we can only name the bee and two or three silk-producing insects. Doubtless the number of species of animals and vegetables which may be reared or cultivated for pleasure or curiosity is very large: witness menageries and zoological and botanical gardens, but I am only speaking here of useful plants and animals, in general and customary employment.

Article III.—Cultivated Plants known or not known in a Wild State

Science has succeeded in discovering the geographical origin of nearly all cultivated species; but there is less progress in the knowledge of species in a natural state – that is wild, far from cultivation and dwellings. There are species which have not been discovered in this condition, and others whose specific identity and truly wild condition are doubtful.

In the following enumeration I have classed the species according to the degree of certainty as to the wild character, and the nature of the doubts where such exist.²¹⁸²

1. Spontaneous species, that is wild, seen by several botanists far from dwellings and cultivation, with every appearance of indigenous plants, and under a form identical with one of the cultivated varieties. These are the species which are not enumerated below; they are 169 in number.

Among these 169 species, 31 belong to the categories A and D, of very ancient cultivation, 56 have been in cultivation less than two thousand years, C, and the others are of modern or unknown date.

2. Seen and gathered in the same conditions, but by a single botanist in a single locality. Three species.

Cucurbita maxima, Faba vulgaris, Nicotiana Tabacum.

3. Seen and mentioned but not gathered in the same conditions by one or two authors and botanists, more or less ancient, who may have been mistaken. Two species.

Carthamus tinctorius, Triticum vulgare.

4. Gathered wild by botanists in several localities under a form slightly different to those which are cultivated, but which most authors have no hesitation in classing with the species. Four species.

Olea europæa, Oryza sativa, Solanum tuberosum, Vitis vinifera.

5. Wild, gathered by botanists in several localities under forms considered by some botanists as constituting different species, while others treat them as varieties. Fifteen species.

Allium ampeloprasum porrum, Cichorium Endivia, var., Crocus sativus, var., *Cucumis melo, Cucurbita Pepo, Helianthus tuberosus, Latuca scariola sativa, Linum usitatissimum annuum, Lycopersicum esculentium, Papaver somniferum, Pyrus nivalis var., *Ribes grossularia, Solanum Melongena, *Spinacia oleracea var., Triticum monococcum.

6. Subspontaneous, that is half-wild, similar to one or other of the cultivated forms, but possibly plants escaped from cultivation, judging from the locality. Twenty-four species.

Agava americana, Amarantus gangeticus, Amygdalus persica, Areca catechu, *Avena orientalis, Avena sativa, *Cajanus indicus, Cicer arietinum, Citrus decumana, Cucurbita moschata, Dioscorea japonica, Ervum Ervilia, Ervum lens, Fagopyrum emarginatum, Gossypium barbadense, Holcus saccharatus, Holcus sorghum, Indigofera tinctoria, Lepidum sativum, Maranta arundinacea, Nicotiana rustica, Panicum miliaceum, Raphanus sativus, Spergula arvensis.

7. Subspontaneous like the preceding, but different enough from the cultivated varieties to lead the majority of authors to regard them as distinct species. Three species.

*Allium ascalonicum (variety of A. cepa?), Allium scorodoprasum (variety of A. sativum?), Secale cereale (variety of one of the perennial species of Secale?).

8. Not discovered in a wild state nor even half-wild, derived perhaps from cultivated species at the beginning of agriculture, but too different not to be commonly regarded as distinct species. Three species.

Hordeum hexastichon (derived from H. distichon?), Hordeum vulgare (derived from H. distichon?), Triticum spelta (derived from T. vulgare?)

9. Not discovered in a wild state nor even half-wild, but originating in countries which are not completely explored, and belonging perhaps to little-known wild species of these countries. Six species.

Arachis hypogea, Carophyllus aromaticus, Convolvulus batatas, *Dolichos lubia, Manihot utilissima, Phaseolus vulgaris.

10. Not found in a wild state, nor even half-wild, but originating in countries which are not sufficiently explored, or in similar countries which cannot be defined, more different than the latter from known wild species. Eighteen species.

Amorphophallus konjak, Arracacha esculenta, Brassica chinensis, Capsicum annuum, Chenopodium quinoa,²¹⁸³ Citrus nobilis, Cucurbita ficifolia, Dioscorea alata, Dioscorea Batatas, Dioscorea sativa, Eleusine coracana, Lucuma mammosa, Nephelium Litchi, *Pisum sativum, Saccharum officinarum, Sechium edule, *Tricosanthes anguina, Zea mays.

Total 247 species.

These figures show that there are 193 species known to be wild, 27 doubtful, as half-wild, and 27 not found wild.

I believe that these last will be found some time or other, if not under one of the cultivated forms, at least in an allied form called species or variety according to the author. To attain this result tropical countries will have to be more thoroughly explored, collectors must be more attentive to localities, and more floras must be published of countries now little known, and good monographs of certain genera based upon the characters which vary least in cultivation.

A few species having their origin in countries fairly well explored, and which it is impossible to confound with others because each is unique in its genus, have not been found wild, or only once, which leads us to suppose that they are extinct in nature, or rapidly becoming so. I allude to maize and the bean (see pp. 387 and 316). I mention also in Article IV. other plants which appear to be becoming extinct in the last few thousand years. These last belong to genera which contain many species, which renders the hypothesis less probable;²¹⁸⁴ but, on the other hand, they are rarely seen at a distance from cultivated ground, and they hardly ever become naturalized, that is wild, which shows a certain feebleness or a tendency to become the prey of animals and parasites.

The 67 species cultivated for less than two thousand years (C, F) are all found wild, except the species marked with an asterisk, which have not been found or which are subject to doubts. This is a proportion of eighty-three per cent.

What is more remarkable is that the great majority of species cultivated for more than four thousand years (A), or in America for three thousand or four thousand years (D), still exist wild in a form identical with some one of the cultivated varieties. Their number is thirty-one out of forty-nine, or sixty-three per cent. In categories 9 and 10 there are only two of these species of very ancient cultivation, or four per cent., and these are two species which probably exist no longer as wild plants.

I believed, à priori, that a great number of the species cultivated for more than four thousand years would have altered from their original condition to such a degree that they could no longer be recognized among wild plants. It appears, on the contrary, that the forms anterior to cultivation have commonly remained side by side with those which cultivators employed and propagated from century to century. This may be explained in two ways: 1. The period of four thousand years is short compared to the duration of most of the specific forms in phanerogamous plants. 2. The cultivated species receive, outside of cultivated ground, continual reinforcements from the seeds which man, birds, and different natural agents disperse and transport in a thousand ways. Naturalizations produced in this manner often confound the wild plants with the cultivated ones, and the more easily that they fertilize each other since they belong to the same species. This fact is clearly demonstrated in the case of a plant of the old world cultivated in America, in gardens, and which, later, becomes naturalized on a large scale in the open country or the woods, like the cardoon at Buenos Ayres, and the oranges in several American countries. Cultivation widens areas, and supplements the deficits which the natural reproduction of the species may present. There are, however, a few exceptions, which are worth mentioning in a separate article.

Article IV.—Cultivated Plants which are Extinct, or becoming Extinct in a Wild State

These species to which I allude present three remarkable characters: —

1. They have not been found wild, or only once or twice, and often doubtfully, although the regions whence they come have been visited by several botanists.

2. They have not the faculty of sowing themselves, and propagating indefinitely outside cultivated ground. In other terms, in such cases they do not pass out of the condition of adventitious plants.

3. It cannot be supposed that they are derived within historic times from certain allied species.

These three characters are found united in the following species: – Bean (Faba vulgaris), chick-pea (Cicer arietinum), ervilla (Ervum Ervilia), lentil (Ervum lens), tobacco (Nicotiana tabacum), wheat (Triticum vulgare), maize (Zea mays). The sweet potato (Convolvulus batatas) should be added if the kindred species were better known to be distinct, and the carthamine (Carthamus tinctorius) if the interior of Arabia had been explored, and we had not found a mention of the plant in an Arabian author.

All these species, and probably others of little-known countries or genera, appear to be extinct or on their way to become so. Supposing they ceased to be cultivated, they would disappear, whereas the majority of cultivated plants have become somewhere naturalized, and would persist in a wild state.

The seven species mentioned just now, excepting tobacco, have seeds full of fecula, which are the food of birds, rodents, and different insects, and have not the power of passing entire through their alimentary canal. This is probably the sole or principal cause of their inferiority in the struggle for existence.

Thus my researches into cultivated plants show that certain species are extinct or becoming extinct since the historical epoch, and that not in small islands but on vast continents without any great modifications of climate. This is an important result for the history of all organic beings in all epochs.

Article V.—Concluding Remarks

1. Cultivated plants do not belong to any particular category, for they belong to fifty-one different families. They are, however, all phanerogamous except the mushroom (Agaricus campestris).

2. The characters which have most varied in cultivation are, beginning with the most variable: a. The size, form, and colour of the fleshy parts, whatever organ they belong to (root, bulb, tubercle, fruit, or seed), and the abundance of fecula, sugar, and other substances which are contained in these parts; b. The number of seeds, which is often in inverse ratio to the development of the fleshy parts of the plant; c. The form, size, or pubescence of the floral organs which persist round the fruits or seeds; d. The rapidity of the phenomena of vegetation – whence often results the quality of ligneous or herbaceous plants, and of perennial, biennial, or annual.

The stems, leaves, and flowers vary little in plants cultivated for those organs. The last formations of each yearly or biennial growth vary most; in other terms, the results of vegetation vary more than the organs which cause vegetation.

3. I have not observed the slightest indication of an adaptation to cold. When the cultivation of a species advances towards the north (maize, flax, tobacco, etc.), it is explained by the production of early varieties, which can ripen before the cold season, or by the custom of cultivating in the north, in summer, the species which in the south are sown in winter. The study of the northern limits of wild species had formerly led me to the same conclusion, for they have not changed within historic times although the seeds are carried frequently and continually to the north of each limit. Periods of more than four or five thousand years, or changements of form and duration, are needed apparently to produce a modification in a plant which will allow it to support a greater degree of cold.

4. The classification of varieties made by agriculturists and gardeners are generally based on those characters which vary most (form, size, colour, taste of the fleshy parts, beard in the ears of corn, etc.). Botanists are mistaken when they follow this example; they should consult those more fixed characters of the organs for the sake of which the species are not cultivated.

5. A non-cultivated species being a group of more or less similar forms, among which subordinate groups may often be distinguished (races, varieties, sub-varieties), it may have happened that two or more of these slightly differing forms may have been introduced into cultivation. This must have been the case especially when the habitation of a species is extensive, and yet more when it is disjunctive. The first case is probably that of the cabbage (Brassica), of flax, bird-cherry (Prunus avium), the common pear, etc. The second is probably that of the gourd, the melon, and trefoil haricot, which existed previous to cultivation both in India and Africa.

6. No distinctive character is known between a naturalized plant which arose several generations back from a cultivated plant, and a wild plant sprung from plants which have always been wild. In any case, in the transition from cultivated plant to wild plant, the particular features which are propagated by grafting are not preserved by seedlings. For instance, the olive tree which has become wild is the oleaster, the pear bears smaller fruits, the Spanish chestnut yields a common fruit. For the rest, the forms naturalized from cultivated species have not yet been sufficiently observed from generation to generation. M. Sagot has done this for the vine. It would be interesting to compare in the same manner with their cultivated forms Citrus, Persica, and the cardoon, naturalized in America, far from their original home, as also the Agave and the prickly pear, wild in America, with their naturalized varieties in the old world. We should know exactly what persists after a temporary state of cultivation.

7. A species may have had, previous to cultivation, a restricted habitation, and subsequently occupy an immense area as a cultivated and sometimes a naturalized plant.

8. In the history of cultivated plants, I have noticed no trace of communication between the peoples of the old and new worlds before the discovery of America by Columbus. The Scandinavians, who had pushed their excursions as far as the north of the United States, and the Basques of the Middle Ages, who followed whales perhaps as far as America, do not seem to have transported a single cultivated species. Neither has the Gulf Stream produced any effect. Between America and Asia two transports of useful plants perhaps took place, the one by man (the Batata, or sweet potato) the other by the agency of man or of the sea (the cocoa-nut palm).