. The elements of botany for beginners and for schools. Botany. SECTION 3.] SEEDLINGS. 21 Some seeds have very little of this deposit, but a comparatively large em- bryo, with its parts more or less developed and recognizable. In others this deposit forms the main bulk of the seed, and the embryo is small or minute, and comparatively rudimentary. The following illustrations exem- plify these various grades. When an embryo in a seed is thus surrounded by a white substance, it was natural to liken the lalter to the white of an egg, and the embryo or germ to the yolk. So the matter around or by t
. The elements of botany for beginners and for schools. Botany. SECTION 3.] SEEDLINGS. 21 Some seeds have very little of this deposit, but a comparatively large em- bryo, with its parts more or less developed and recognizable. In others this deposit forms the main bulk of the seed, and the embryo is small or minute, and comparatively rudimentary. The following illustrations exem- plify these various grades. When an embryo in a seed is thus surrounded by a white substance, it was natural to liken the lalter to the white of an egg, and the embryo or germ to the yolk. So the matter around or by the side of the embryo was called the Albumen, I. e. the white of the seed. The analogy is not very good ; and to avoid ambiguity some botan- ists call it the Endosperm. As that means in English merely the inwards of a seed, the new name is little better than the old one ; and, since we do not change names in botany except when it cannot be avoided, this name of albu- men is generally kept up. A seed with such a deposit is albuminous, one with none is exal- buminous. 32. The Albumen forms the main bulk of the seed in wheat, maize, rice, buckwheat, and the like. It is the floury part of the seed. Also of the cocoa-nut, of coffee (where it is dense and hard), etc. ; while in peas, beans, almonds, and in most edible nuts, the store of food, al- though essentially the same in nature and in use, is in the embryo itself, and therefore is not counted as anything to be separately named. In both forms this concentrated food for the germinating plant is food also for man and for animals. 33. For an albuminous seed with a well-developed embryo, the com- mon Morning Glory (Ipomoea purpurea. Fig. 40-43) is a convenient exam- ple, being easy and prompt to grow, and having all the parts well apparent. The seeds (duly soaked for examination) and the germination should be compared with those of Sugar and Red Maple (19-21). The only essen- tial difference is that here the embryo is surrounded by
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