. Elementary botany . Fig. 258. Fig. 259. Fig. 260. Fig. 261. Fig. 262. Sterile scale. Scale with Seeds have Back of scale Winged Seeds imdevel- we 11-developed split off from with small cover seed free from oped. seeds. scale. scale. scale. Figs. 258-262.—White pine showing details of mature scales and seed. of the scales, just as they are beginning to spread, or before the seeds have scattered, we shall find the seeds at- tached to the upper surface at the lower end. There are two seeds on each scale, one at each lower angle. They are ovate in outline, and shaped somewhat like a biconvex len
. Elementary botany . Fig. 258. Fig. 259. Fig. 260. Fig. 261. Fig. 262. Sterile scale. Scale with Seeds have Back of scale Winged Seeds imdevel- we 11-developed split off from with small cover seed free from oped. seeds. scale. scale. scale. Figs. 258-262.—White pine showing details of mature scales and seed. of the scales, just as they are beginning to spread, or before the seeds have scattered, we shall find the seeds at- tached to the upper surface at the lower end. There are two seeds on each scale, one at each lower angle. They are ovate in outline, and shaped somewhat like a biconvex lens. At this time the seeds easily fall away, and may be freed by jarring the cone. As the seed is detached from the scale a strip of tissue from the latter is peeled off. This forms a " wing " for the seed. It is attached to one end and is shaped something like a knife blade. On the back of the scale is a small appendage known as the cover scale. 416. Formation of the female pine cone.—The female flowers begin their development rather late in the spring of the year. They are formed from terminal buds of the higher branches of the tree. In this way the cone may terminate the main shoot of a branch, or of the Fig, 2r,3. lateral shoots in a whorl. After growth has proceeded Female (ones of the for some time in tin- spring, the terminal portion begins pine at tunc of pollina-
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisher, booksubjectbotany
