. High school botanical note book [microform]. Botany; Botanique. GLOSSARY OF III NircMoijs : tlio lioily of iho ovulo wiiliin tlio coats (Fig. 172, h), EMimvo-sAc : tlio lar(.e coll in the nucleus in whicli the vo'uuk plant is ik'Vflojicd (Fif;. Vrl, cm). : tlio ],oition where the two coats are Mended together (Fig. 17:?, c). Kinds of Ovule. OiiTiiOTUOi'or-s : when the o^ ule is erect, and the micropylo is as far as i)ossiblo from the funiculus or i)oint of attach- ment (Fig. 17:2). AxATiiopous: when the ovule is completely inverted or bent uiion itself so as to bring the micropylo cl
. High school botanical note book [microform]. Botany; Botanique. GLOSSARY OF III NircMoijs : tlio lioily of iho ovulo wiiliin tlio coats (Fig. 172, h), EMimvo-sAc : tlio lar(.e coll in the nucleus in whicli the vo'uuk plant is ik'Vflojicd (Fif;. Vrl, cm). : tlio ],oition where the two coats are Mended together (Fig. 17:?, c). Kinds of Ovule. OiiTiiOTUOi'or-s : when the o^ ule is erect, and the micropylo is as far as i)ossiblo from the funiculus or i)oint of attach- ment (Fig. 17:2). AxATiiopous: when the ovule is completely inverted or bent uiion itself so as to bring the micropylo close to the point of attachment (Fig. 17;i). In this case the funiculus becomes fused with the i)rimine on one side, forming the raiihe (Fig. 173. ;•). Cami'vi.()tuoi'I)i;s : when the ovule is half bent over (Fig. 17)). Fertilization. Ovules are converted into seeds by the action of pollen upon t horn. Pollen grains fall ujion the stigma which is moist and retains them. The grains begin to grow as shown in Fig. 150, the inner coat being ]irotruded as a slender tube which nuikes its way down through the style into the ovary, and then through the micropylo of the ovule, finally attaching itself to the surface of the embryo-sac, and carrying the contents of the jiollon-grain with it. Presently growth begins inside the emljryo-sac, and soon the embryo is formed. It is the presence of the embryo which marks the distinction between an ovule and a seed. In most cases the ovulo is fertilized by pollen brought from another Hower of tlie same species (cross-fertiliza- tion), because very commonly the pollen of its own flower is ready either too soon or too late to be of use; that is, the ])ollen and the stignni in the same flower do not com- monly mature at the same time. Plants are Eiitomophilom, when thoy depend upon insects to carry the pollen from flower to flower, and Ammophilous, when this service is performed by the wind. THE FRUIT. Definition. The fruit is the ripened pistil tog
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1895
