The elements of botany for The elements of botany for beginners and for schools elementsofbotany00grayuoft Year: [1887] 52 LEAVES. [section 7. 132. In the other case (as in Fig. 74, 129-132), the veins branch off from three, five, seven, or nine ribs, which spread from the top of the leaf- stalk, and run through the blade like the toes of a web-footed bird. Hence these are said to be Falmately or Digitately veined, or (since the ribs di- verge like rays from a centre) Radiate-wined. 133. Since the general outline of leaves accords with the frame-work or skeleton, it is plain that feather-vein
The elements of botany for The elements of botany for beginners and for schools elementsofbotany00grayuoft Year: [1887] 52 LEAVES. [section 7. 132. In the other case (as in Fig. 74, 129-132), the veins branch off from three, five, seven, or nine ribs, which spread from the top of the leaf- stalk, and run through the blade like the toes of a web-footed bird. Hence these are said to be Falmately or Digitately veined, or (since the ribs di- verge like rays from a centre) Radiate-wined. 133. Since the general outline of leaves accords with the frame-work or skeleton, it is plain that feather-veined (or penni-vei>ied) leaves will incline to elongated shapes, or at least to be longer than broad; while in radiate- veined leaves more rounded forms are to be expected. A glance at the following figures shows this. 134. Forms of Leaves as to General Outline. It is necessary to give nauies to the principal shapes, and to define them rather precisely, since they afford easy murks for distinguishing species. The same terms are used 115 116 117 118 119 120 for all other flattened parts as well, such as petals; so that they make up a great part of the descriptive language of Botany. It will be a good exer- cise for young students to look up leaves answering to these names and definitions. Beginning with the narrower and proceeding to the broadest forms, a leaf is said to be Linear (Fig. 115), when narrow, several times longer than wide, and of the same breadth throughout. Lanceolate, or Lance-shaped, when conspicuously longer than wide, and tapering upwards (Fig. 116), or both upwards and downwards. Oblong (Fig. 117), when nearly twice or thrice as long as broad. Elliptical (Fig. 118) is oblong vrith a flowing outline, the two ends alike in width. Ocal is the same as broadly elliptical, or elliptical with the breadth con- siderably more than half the length. • Omte (Fig. 119), when the outline is like a section of a hen's egg lengthwise, the broader end downward. Orbicular
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