The Nursery-Manual —— A Complete Guide to the Multiplication of Plants

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ISBN: 9781330072400 出版年：2016 页码：503 L H Bailey Forgotten Books

The earth is clothed with plants. All these plants are the results of propagation. Plants perpetuate themselves and increase their numbers by many means. These means are sexual (by seeds and some kinds of spores), and asexual (by vegetative parts). Seeds are the results of the fertilization of the ovule (strictly Of the egg-nucleus of the ovule) by the germ-nucleus Of the pollen-grain. The ovule, with its integuments and perhaps with adhering parts, ripens into the seed. Of many forms, sizes and colors are the seeds of plants. SO various are they that we visualize no seed-form, as we visualize heart-form or rose form, and many Of them are hardly recognizable. Yet they all have this in common, that they contain a dormant or quiescent embryo. This embryo is a rudimentary or minute plant. When the conditions are right for the plantlet to resume its growth, we say that the seed germinates.