The vegetable world : being a history of plants / with their structure and peculiar properties. Adapted from the work of Louis Figuier ; with a glossary of botanical terms.

  • Figuier, Louis, 1819-1894
Date:
[1869?]
Catalogue details

Licence: Public Domain Mark

Credit: The vegetable world : being a history of plants / with their structure and peculiar properties. Adapted from the work of Louis Figuier ; with a glossary of botanical terms. Source: Wellcome Collection.

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    root, lateral roots branch out more or less regularly, and these lateral roots subdivide again and again. In many cases, especially at first, the lateral roots issue from the tap-root with great order and regu- larity, as much as in the arrangement of the branches of a young fir-tree; in older plants this order is lost. The tap- root is conspicuous in the dock (Rumex) and in seedling fruit-trees ; its upper portion in many cultivated plants, such as the beet and carrot, expands under cultivation, and becomes abnormally fleshy (Fig. 6). But all roots are not planted in the soil. There are some plants which develop roots in water, as the Duckweed (Letnna), Fig. 5, which never touches the earth. Others nourish themselves on the tissues of .other plants, as the Mistletoe, a singular parasitic plant, which forms tufts or branches of a delicate pale green, attaching itself to apple- trees, poplars, and a number of other trees. Some roots appear, moreover, to have no other function than to fix the plants to the soil: they seem to contribute nothing to their nourishment. In the Museum of Natural History of Paris there has been for some years a magnificent Peruvian cactus, of an extraordinary height, which has been growing vigorously, throwing out enormous branches with great rapidity. Its roots are shut up in a box of three feet square, filled with earth, which has never been renewed and never watered. It is therefore evident that in this case the roots have little to do with the nourishment of the plant. Other instances confirm these inferences. “ In a country where many months pass without a drop of rain falling,” says Auguste de St.- Hilaire, “ I have seen, during the dry season, cactuses covered with flowers, maintaining themselves on the burning rocks by the aid of a few weak slender roots, which sink into the dried-up humus which has found its way into the narrow clefts of the rock.” Nevertheless, most plants are nourished, to a large extent, through their roots. Other plants, like the Screw-pine (.Pandanus), and the Mangrove (Rhizophora), from their habit of emitting roots from the stem, which l ig. 5.—Duckweed (Lenina).