. The elements of botany for beginners and for schools. Botany. 58 two cotyledons even in a Pine-embryo, but tbese divided or split up con- genitally so as to imitate a greater number. But as leaves are often in vrhorls on ordinary stems, they may be so at tlie very beginning. 40. Monocotyledonous (meaning with _ single cotyledon) is tlie name of the one-coty- ledoaed sort of embryo. This goes along with peculiarities in stem, leaves, and flowers ; which all together associate such plants into a great class, called Monocotyledonous Plants, or, for shortness, Monocotyls. It means merely that th
. The elements of botany for beginners and for schools. Botany. 58 two cotyledons even in a Pine-embryo, but tbese divided or split up con- genitally so as to imitate a greater number. But as leaves are often in vrhorls on ordinary stems, they may be so at tlie very beginning. 40. Monocotyledonous (meaning with _ single cotyledon) is tlie name of the one-coty- ledoaed sort of embryo. This goes along with peculiarities in stem, leaves, and flowers ; which all together associate such plants into a great class, called Monocotyledonous Plants, or, for shortness, Monocotyls. It means merely that the leaves are alternate from the very first. 41. In Iris (Fig. 58, 59) the embryo ia the seed is a small cyHuder at one end of the mass of the albumen, with no appai'ent dis- tinction of parts. The end which almost touches the seed-coat is caulicle; the other end belongs to the solitary cotyledon. In germination the whole lengthens (but mainly the cotyledon) only enough to push the proximate end fairly out of the seed : from this end the root is formed; and from a little higher the plumule later emerges. It would appear, therefore, that the cotyledon answers to a minute leaf rolled up, and that a chink through which the plumule grows out is a part of the inrolled edges. The embryo of Indian Corn shows these parts on a larger scale and in a more open state (Fig. 66- 68). There, in the seed, the cotyledon remains, imbibing nourishment from the softened albu- men, and transmitting it to the growing root below and new-forming leaves above. 42. The general plan is the same in the Onion (Fig. 60-65), but witn a striking difl"erence. The embryo is long, and coiled in the albumen of the seed. To ordinary examination it shows no distinction of parts. But germination plainly shows that all except the lower end of it is cotyledon. For after it has lengthened into a long thread, the chink from which the Fig. 56. Section of a Pine-seed, showing its polycotyledonous embryo in the centre
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Keywords: ., bookpublishernewyorkamericanboo, booksubjectbotany, bookyear1887
