. The elements of structural botany [microform] : with special reference to the study of Canadian plants, to which is added a selection of examination papers. Plant anatomy; Botany; Plantes; Botanique. Oi' STKL'CTLUAL BOTANY. 73. leaves, tlie Beecli, Mullein, and Willow supply familiar inbtanccK. The Mallow, ^laple, Grape, Cunaiit, antl Gooseberry '- ,-j'-j^ have simple radiate-veined leaves. ^ Swect-lirier (Fig. 4M), Mouutain- Ash, and Rose have compound ])innate leaver, whilst those of Virginia-Creeper (Fig. HH)), ^'" ^*'^* Ilorse-Chestnut, and IJcmp are compountl digitate. As
. The elements of structural botany [microform] : with special reference to the study of Canadian plants, to which is added a selection of examination papers. Plant anatomy; Botany; Plantes; Botanique. Oi' STKL'CTLUAL BOTANY. 73. leaves, tlie Beecli, Mullein, and Willow supply familiar inbtanccK. The Mallow, ^laple, Grape, Cunaiit, antl Gooseberry '- ,-j'-j^ have simple radiate-veined leaves. ^ Swect-lirier (Fig. 4M), Mouutain- Ash, and Rose have compound ])innate leaver, whilst those of Virginia-Creeper (Fig. HH)), ^'" ^*'^* Ilorse-Chestnut, and IJcmp are compountl digitate. As has already been pointed out, the leaves of Mouo- cotyledouous plants are almost invariably straight- veined. 108. In addition to the venation, the description of a simple leaf includes particulars concerning. (1) the general outline, (2) the edge or margin, (li) the point or apex, (4) the base 104. Outline. As to outline, it will be convenient to consider first the forms assumed by leaves without lobes, and whose margins are therefore more or less continuous. Such leaves are of three sorts, viz : thos3 in which both ends of the leaf are alike, those in which the apex is narrower than the base, and those in which the apex is broader than the base. 105. In the first of these three classes, it is evident that any variation in tlie outline will depend altogether on the relation between the length and the breadth of the leaf. When the leaf is extremely narrow in com- parison with its length, as in the Pine, it is v/^irjlar or )U'e(IU']>ed (Fig. 110). As the width increases, we pass through the forms known as liufu-, obloutj, cvcd, and finally orbicular, in which the width and length are nearly, or quite equal (Fig. 111). !5ll!&. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Macoun, John, 1831-1920
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, booksubjectpl
