. Outlines of plant life : with special reference to form and function . Botany. VEGETATIVE REPRODUCTION. 199 containing the ovules, surmounted by (2) a slender part of variable length, the style, which is terminated by (3) a rough, sticky, or branched part, the j/z^fwa. (See figs. 152,156.) 283. Stigma and style.—The stigma may take the form of a knob, a ridge, a straight or wavy line, or be lobed or branched. However compact, it is usually roughened by the prolongation of its surface cells into rounded, pointed, or hair-like extensions (fig. 154), which frequently secrete a sticky fluid. Its
. Outlines of plant life : with special reference to form and function . Botany. VEGETATIVE REPRODUCTION. 199 containing the ovules, surmounted by (2) a slender part of variable length, the style, which is terminated by (3) a rough, sticky, or branched part, the j/z^fwa. (See figs. 152,156.) 283. Stigma and style.—The stigma may take the form of a knob, a ridge, a straight or wavy line, or be lobed or branched. However compact, it is usually roughened by the prolongation of its surface cells into rounded, pointed, or hair-like extensions (fig. 154), which frequently secrete a sticky fluid. Its purpose is to secure the adhesion of the pollen spores brought to it by various agents, among the most important of which are the wind and insects. The style may be thick or slender, long or short; branched or unbranched, hollow or solid. It is frequently wanting. 284. Simple and compound pistils. —When several carpels are present in one flower they may form as many separate simple pistils as there are carpels. If numerous, the axis will be enlarged or elongated to accom- modate them. (See ^ 296, and fig. 173.) Instead of forming separate pistils, the carpels may be united to form a single compound pistil. The union of the carpels may be only at the base; or it. Fig. 154.—One of the hairs from the stigma of com cockle {Lychnis githa^o) to which a pollen grain ad- heres. The pollen tube has penetrated the hair and is making its way down the style. Magnified 175 diam. —After Strasburger. the ovules (= little eggs) were like the eggs of birds, an idea which was further carried out in the name albumen given to the food stored in the seed. (See \ 305.) To avoid confusion with the true ovary in which the real egg is produced, I use the name ovulary—, the organ which produces ovules. The word ovule, though as bad in etymology as ovary, is convenient, and does not lead to any Please note that these images are extracted from scanned page images that may have b
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