. Nature and development of plants. Botany. 374 THE SEED OF FINALES the sporangia. The sporophylls or their outgrowths often be- come greatly enlarged, forming the hard, woody scales of the cones (Fig. 258, B), or they may become fleshy and fuse, forming a berry-like fruit, as in the juniper (Fig. 260, 7). When this growth has been completed, the woody sporophylls or scales of the strobilus dry out, and becoming hygroscopic, they spread apart on dry days, thus permitting the scattering of the seeds by the winds (Fig. 258, A). Many of the fleshy fruits are eaten by birds and the hard nut-like s
. Nature and development of plants. Botany. 374 THE SEED OF FINALES the sporangia. The sporophylls or their outgrowths often be- come greatly enlarged, forming the hard, woody scales of the cones (Fig. 258, B), or they may become fleshy and fuse, forming a berry-like fruit, as in the juniper (Fig. 260, 7). When this growth has been completed, the woody sporophylls or scales of the strobilus dry out, and becoming hygroscopic, they spread apart on dry days, thus permitting the scattering of the seeds by the winds (Fig. 258, A). Many of the fleshy fruits are eaten by birds and the hard nut-like seeds are distributed in this ~FiG. 258. A, mature strobilus of pine with open scales to permit the "scattering of the seeds. B, scale from strobilus showing the winged seeds â developed from the two sporangia. C, a seed with wing-like outgrowth, as it escapes from strobilus. The stages in the development of the seed, outlined above, are very much prolonged in many of the pines. The microspores on reaching the megasporangia, in the spring, develop only a short tube cell during the first season and not until about the first of July of the following season are the male and female gametes mature and ready for fertilization. The seeds are matured during the following season, over two years after the appearance of the strobilus. Accordingly, three stages in the development of the strobilus of megasporophylls may be seen on certain species of pine in the early summerâvery small ones that received the microspores in the spring, larger ones in which fertilization and the formation of the embryo is being effected and older stro- bili in which the seeds are approaching maturity (Fig. 252). When the conditions are favorable the embryo renews its 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 Curti
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