. The elements of botany for beginners and for schools. Botany. SECTION 15.] EMBRYO. 127. 386. The Kernel, or Nucleus, is the whole body of the seed within the coats. Inmany seeds the ker- nel is all Embryo; in others ' a large part of it is the AU t bumen. For example, in Fig. 423, it is wholly embryo; in Fig. 422, all but the small speck (_^) is albumen. 387. The Albumen or Endosperm of the seed is sufficiently charac- terized and its office explained in Sect. III., 31-35. 388. The Embryo or Germ, which is the rudimentary plantlet and the final result of blossoming, and its development in ge
. The elements of botany for beginners and for schools. Botany. SECTION 15.] EMBRYO. 127. 386. The Kernel, or Nucleus, is the whole body of the seed within the coats. Inmany seeds the ker- nel is all Embryo; in others ' a large part of it is the AU t bumen. For example, in Fig. 423, it is wholly embryo; in Fig. 422, all but the small speck (_^) is albumen. 387. The Albumen or Endosperm of the seed is sufficiently charac- terized and its office explained in Sect. III., 31-35. 388. The Embryo or Germ, which is the rudimentary plantlet and the final result of blossoming, and its development in germination have been extensively illustrated in Sections II. and III. Its essential parts are the Radicle and the Cotyledons. 389. Its Radicle or Caulicle (the former is the terra long and gener- ally used in botanical descriptions, but the latter is the more correct one, for it is the initial stem, wiiich merely gives origin to the root), as to its position in the seed, always points to and lies near the micropyle. In re- lation to the pericarp it is Superior, when it points to the apex of the fruit or cell, and Inferior, when it points to its base, or downward. 390. The Cotyledons have already been illustrated as re- spects their number, — giving the important distinction of Dicoty- ledonous, Polycotyledonous and Monocotyledonous embryos (36-43), — also as regards tlieir thickness, "^lieihev foliaceous or Jfes/iy ; and some of the very various shapes and adaptations to the seed have been figured. They may be straight, or folded, or rolled up. In the latter case the cotyledons may be rolled up as it were from one margin, as in Calycanthus (Fig. 424), or from apex to base in a flat spiral, or they may be both folded (^plicate) and rolled up {convolute), as in Sugar Maple (Fig. 11.) In one very natural family, the Cruciferse, two ditfereut modes prevail in the way the two cotyledons are brought round against the radicle. In one series they are. Please note that these ima
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Keywords: ., bookpublishernewyorkamericanboo, booksubjectbotany, bookyear1887
