Plants and their ways in South Africa . Fig. io.—Seed of Mes-embrianthemum withcurved embryo. Fig. II.—Seed of Zea mays, a, embryo at one sideof endosperm ; b, embryo removed; c, seed cutthrough, showing plumule, radicle, and side roots. mays). Notice a small raised place on one side toward the smaller end. By soaking the seed and removing the coat this little body may be removed. It is the embryo. The greater part of the seed is filled with endosperm. The embryo has but one cotyledon, which lies close to the endosperm on one side, and on the other is joined to the plumule and radicle. They ar
Plants and their ways in South Africa . Fig. io.—Seed of Mes-embrianthemum withcurved embryo. Fig. II.—Seed of Zea mays, a, embryo at one sideof endosperm ; b, embryo removed; c, seed cutthrough, showing plumule, radicle, and side roots. mays). Notice a small raised place on one side toward the smaller end. By soaking the seed and removing the coat this little body may be removed. It is the embryo. The greater part of the seed is filled with endosperm. The embryo has but one cotyledon, which lies close to the endosperm on one side, and on the other is joined to the plumule and radicle. They are so covered by the folded cotyledon or scutellum that only the tips can be seen. The large seeds of the April Fool (Hcemanthus) havebut one cotyledon. The embryo is a small rod-shaped bodylying in the centre of the endosperm. Around the endosperm. Fig. 12.—HcEmanthus seed. a,embryo ; b, endosperm ; c, foodoutside the endosperm partlyused ; d, seed-coat. lo Plants and their Ways in South Africa there is another food storing region (perisperm). It can beseen plainly in young seeds, and its position will remind you ofthe thin layer in the pine seed.^ Examine a date and compare the seed with that ofHcemanthus. Water Uintjes {Aponogeton) has one large green coty-ledon, a thin plumule, and a very small food is all stored in the cotyledon. Plants which have two cotyledons are calledDicotyledons, those with only one are Mono-cotyledons, It is an important monocotyledons have endosperm. WaterUintjes [Aponogeton) is an exception. Theplants in each group have other characters incommon which we shall find out later. In Hcemanthus and date the embryos are sovery small that the food supply seems sarily generous ; but it takes a long while for thedate to get a firm footing in the soil, and the A
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1915
