Page:Encyclopædia Britannica, Ninth Edition, v. 4.djvu/162

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152 BOTANY [REPRODUCTIVE ORGANS. mass, formed by the placentas. The name is usually given to such fruits as the Gooseberry (fig. 302) and Currant, in which the ovary is inferior, and the placentas are parietal, the seeds being ultimately detached from the placenta, and Fig. 300. Fig. 302. Fig. 301. Fig. 303. FIG. 300. Follicle of Columbine (AquHeyia vulgaris), consisting of a polyspcrmul carpel, opening by the ventral suture. FIG. 301. Apocarpous fruit of Columbine (AquUegiawlgari*), consisting of five separate mature carpels, with styles nnd stigmas. FIG. 302. Fruit of the Gooseberry (Kibes Grossularia), cut vertically, showing the seeds attached to parietal placentas, and immersed in pulpy matter, which is formed partly from the endocaip and partly from the testa of the seed. The fruit is called a bacca. FIG. 303. Section of the fruit of the Apple (Ft/rus Mains), consisting of a fleshy covering partly formed by the calyx and disk, and five cavities in the centre with seeds. The fruit is called a pome. lying loose in the pulp. Others have applied it also to those in which the ovary is superior, as in the Grape, Potato, and Ardisia, and the placentas are central or free central. The latter are frequently separated under the name uva (grape). In general, the name of baccate or berried is applied to all pulpy fruits. In the Pomegranate there is a peculiar baccate many-celled inferior fruit, having a tough rind, enclosing two rows of carpels placed one above the other. The seeds are immersed in pulp, and are attached irregularly to the parietes, base, and centre of the loculi. The fruit has been called balausta, and the tough rind is called malicorium. In the Baobab there is a multilocular syncarpous fruit, in which the seeds are immersed in pulp, to which the name amphisarca is given. The pepo or peponida, another indehiscent syncarpous fruit, is illustrated by the fruit of the Gourd, Melon (fig. 262), and other Cucurbitacete. It is formed of three carpels, to which the calyx is superior ; the rind is thick and fleshy, partly formed by the calyx ; and there are three or more seed-bearing parietal placentas, either surrounding a central cavity, or prolonged inwards into it. The fruit of the Papaw resembles the pepo, but the calyx is not superior. The hesperidium is the name given to such indehiscent syncarpous fruits as the Orange, Lemon, and Shaddock, in which the epicarp and mesocarp form a separable rind, and the endocarp sends prolongations inwards, forming triangular divisions, to the inner angle of which the seeds are attached, pulpy cells being developed around them. Both pepo and hesperidium may be considered as modifica tions of the berry. The pome, seen in the Apple, Pear, Quince, Medlar, and Hawthorn, is a fleshy indehiscent syncarpous fruit with the calyx attached, and has an outer skin or epicarp, a fleshy mesocarp, and a scaly or horny endocarp (the core] enclosing the seeds (fig. 303). Some look upon the so-called epicarp and mesocarp as formed by the prolonged receptacle on the inner surface of which a fleshy lining is developed, while the endocarp represents the true carpels. In this view the endocarp might be regarded as consisting of a number of indehiscent follicles (usually five) surrounded by a succulent receptacle. In the Medlar the endocarp (or what may be called the true pericarp) is of a stony hardness, while the outer succulent covering is open at the summit. The stones of the Medlar are called pyrence ; some apply the term nuculanium to the Medlar. Taking this view of the pome it may be said to resemble in a manner the fruit of the Rose, the cynarrhodum producing aclieiies, and the pome closed follicles. The name capsule is applied generally to a 1 ! dry syn- PMe X. carpous fruits, which dehisce by valves of whatever kind. fi s- - It may thus be unilocular or multilocular, monospermous ^ at r or polyspermous. The true valvular capsule is observed c in Colchicum (fig. 284), Lily, and Iris (fig. 28G). Thoporofe capsule is seen in the Poppy (fig. 2G9), Antirrhinum majus, Plntt; I. and Campanula persicifolia. In Campanula the pores occur at the base of the capsule, and it has been designated a diplotegia. When the capsule opens by a lid, or by circumscissile dehiscence, it is called a pyxidmm, as in Anagallis arvensis, Henbane (fig. 291), and Monkey pot (Lecythis). The capsule assumes a screw-like form in Helicteres, and a star-like or stellate form in Illicium anisatum. In certain instances the cells of the capsule separate from each other, and open with elasticity to scatter the seeds. This kind of capsule is met with in the Sandbox tree (Hura crepitans), and other Euphorbiaceaj, Plate XIII where the cocci, containing each a single seed, burst asunder fi g- 7 - with force ; and in Gerauiaceai, where the cocci, each con- taining, when mature, usually one seed, separate from the carpophore, become curved upwards by their adherent styles, and open by the ventral suture (fig. 152). In the former case the fruit collectively has been called rerjina. Fig. 305. Fig. 304. Fig. 306. Fig. 307. FIG. 304. Compound ovary (siliquu) of Wallflower (Chetranthus), consisting of ut least two carpels united. One valve has been removed to show the partition or replum cl, formed of a double layer from the placentae en on either side, to which the ovules ov are attached by means of funiculi. The style and stigir.a s are at the upper part of the ovary. FIG. 305. Silicula of Whitlow-grass (Draba), opening by two flat vnlves o from below upwards, leaving the parietal placentas pi in the centre, united by a membrane or replum. The partition of the seed-vessel is broad, and hence. the name latiscptae. FIG. 306. Silicula or pouch of Shepherd s purse (CapseUa), opening by two folded valves, which separate from below upwards. The phragma is narrow, and hence the name angustiseptee. FIG. 307. Fruit of the Pine-apple (Ananassa saliva), consisting of numerous flowers and bracts united together so as to form a collective or anthocarpous fruit. The crown of the Pine-apple, c, consists of a series of empty bracts prolonged beyond the fruit. The siliqiia is a dry syncarpous bicarpellnry bilocular polyspermal fruit with a replum, dehiscing by two valves from below upwards, the valves separating from the placentas and leaving them united by the replum. The seeds are attached on both sides of the replum, either in

one row or in two. When the fruit is long and narrow it