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 Rh, which season therefore is proper for their transplantation. After they have begun to throw out new fibres, it is more or less dangerous, or even fatal, to remove them. Very young annual plants, as they form new fibres with great facility, survive transplantation tolerably well, provided they receive abundant supplies of water by the leaves till the root has recovered itself.

Botanists distinguish several different kinds of roots, which are necessary to be known, not only for botanical purposes, but as being of great importance in agriculture and gardening. The generality of roots may be arranged under the following heads.

1. Radix fibrosa. A Fibrous Root. The most simple in its nature of all, consisting only of fibres, either branched or undivided, which convey nourishment directly to the basis of the stem or leaves. Many grasses, as Poa annua, Engl. Bot. t. 1141, and the greater part of annual herbs, have this kind of root. The radical fibres of grasses that grow in loose sand are remarkably downy, possibly for the purpose of fixing them more