. Introduction to structural and systematic botany, and vegetable physiology. Botany. 70 DEVELOPMENT OP FLOWERING OR PII^NOGAMOUS. be destitute of organs ; and it is only in tlie higher Cryptogamous plants, such as Mosses and Ferns, that the familiar organs of ordi- nary vegetation appear as separate parts of the plant, viz. the root, stem, and leaves. In the higher grade (i. e. in Phaenogamous Plants) these three parts are well defined, and always present, in some form or other ; — a few anomalous instances excepted, such as the common Duck-weed, for example (Fig. 102). Here stem and leaf are
. Introduction to structural and systematic botany, and vegetable physiology. Botany. 70 DEVELOPMENT OP FLOWERING OR PII^NOGAMOUS. be destitute of organs ; and it is only in tlie higher Cryptogamous plants, such as Mosses and Ferns, that the familiar organs of ordi- nary vegetation appear as separate parts of the plant, viz. the root, stem, and leaves. In the higher grade (i. e. in Phaenogamous Plants) these three parts are well defined, and always present, in some form or other ; — a few anomalous instances excepted, such as the common Duck-weed, for example (Fig. 102). Here stem and leaf are as it were blended, in the manner of a Liverwort, to form a flat green body, which floats on the water, exposing the upper sur- face like a leaf to the light, while one or more roots proceed from the lower, and a small and simple flower at length makes its appearance on some part of the margin. This is an extremely simplified state of a Phsmogamous plant. 115. Ordinarily, not only are the root, stem, and foliage distinct and separate from each other, but also distinct from the apparatus for reproduction. So that the plant is composed of two kinds of or- gans, viz. Organs of Vegetation and Organs or Reproduction. 116. The Organs of Vegetation are the Root, Stem, and Leaves (110). These are so called because they are jointly concerned in the nutri- tion and growth of the plant, and in the performance of all its char- acteristic functions, and they are all that is so concerned. Making up as they do the entire vegetable, and repeated under varied forms throughout its whole development, they are also termed the Funda- mental Organs of plants. 117. The Organs of Reproduction in the simplest Cryptogamous plants are not distinct from those of vegetation; but in most plants, even of the lowest families, the cells for reproduction are different in appearance and in the mode of their formation from those which serve for vegetation. These reproductive cells, or Spores, with the apparatu
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