. Elementary botany [microform]. Botany; Botanique. CHAPTER XII OVULE—FERTILISATION—SEED—FRUIT OVULE. An ovule (figs. 108, iii) is a more or less egg-shaped body attached^ to the placenta by means of a stalk—the fimicle (/). The main body of the ovule consists of a central egg-shaped 108 loQ ' no mass — the niicellus — which is surrounded by one or two coats — the integuments {in). Each integument is attached by its base to the nucellus, but elsewhere it surrounds the nucellus like a narrow- mouthed bag, which is open at the top. The opening at the top of the int*'gument or integu- ments is th
. Elementary botany [microform]. Botany; Botanique. CHAPTER XII OVULE—FERTILISATION—SEED—FRUIT OVULE. An ovule (figs. 108, iii) is a more or less egg-shaped body attached^ to the placenta by means of a stalk—the fimicle (/). The main body of the ovule consists of a central egg-shaped 108 loQ ' no mass — the niicellus — which is surrounded by one or two coats — the integuments {in). Each integument is attached by its base to the nucellus, but elsewhere it surrounds the nucellus like a narrow- mouthed bag, which is open at the top. The opening at the top of the int*'gument or integu- ments is the micropyle {m); it allows free com- munication between the nucellus and the chamber In the nucellus itself, near the micropyle, there is a minute clear space. This is in reality a closed bladder, and is termed the embryo-sac. There are three types of ovules, whose forms are best explained by the figures given. (i) An orthotropous ovule is one in which the stalk (funicle) is in the same straight line as the straight nucellus (figs. 108, 111). (2) An atiatropous ovule is one in which the nucellus itself is straight, but is inverted, and consequently .appears to be attached by its side 84. Figs. loS-iio.—Ovules. - , Figs. 111-113.—Vertical sections through ovules. 01 the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Groom, Percy, 1865-1931; Penhallow, D. P. (David Pearce), 1854-1910. A manual of the more common herbaceous plants of Quebec and Ontario; Gray, Asa, 1810-1888. Elements of botany. Toronto : Copp, Clark
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