The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . te. In Compositas, the fruit,IIX. which is sometimes called cypsela, is an acho^nium (), to which the pappose or obsolete calyx remains ad-herent. Such is also tlie nature of the fruit in the pericarp is thin, and appears like a bladdersurrounding the seed, the achaenium is termed a ntricle,as in Amarantaceae. When the pericarp is extehded inthe form of a winged appendage, a samara or samaroidachccnuim is produced, as in the Ash (fig. 281), CommonSycamore (fig. 296), and Hiraea. In
The Encyclopaedia Britannica; .. A dictionary of arts, sciences and general literature . te. In Compositas, the fruit,IIX. which is sometimes called cypsela, is an acho^nium (), to which the pappose or obsolete calyx remains ad-herent. Such is also tlie nature of the fruit in the pericarp is thin, and appears like a bladdersurrounding the seed, the achaenium is termed a ntricle,as in Amarantaceae. When the pericarp is extehded inthe form of a winged appendage, a samara or samaroidachccnuim is produced, as in the Ash (fig. 281), CommonSycamore (fig. 296), and Hiraea. In these cases there areusually two achsenia united, one of which, however, as inFraxinus oxyphylla (fig. 281), may be abortive. The wingis either dorsal, that is, it is a prolongation from the medianvein (fig. 296, a) or it is marginal, that is, formed by thelateral veins. It surrounds the fruit longitudinally in theElm. When the pericarp becomes so incorporated with the• seed as to be inseparable from it, as in grains of Wheat,Maize, Oats (fig. 297), and other Grasses, then the name. Tig. 297. Fig. 298. Fig. 299. Fig. 297.—Caryopsia or single-seeded pcrain of Oats (Avena). The fruit and seedava Incorporated. The pericarp o bears the styles and stigmas, and enclosesthe seed t, with its albumen, or perisperm, a, and its embryo, consisting of thecotyledon c, the fjemmule ?, and the root r. Iio. 298.—Calyi and fruit of Comfrcy (Sgmplit/inm), cut vertically. The fruit Isdivided by the folding of the ovary into four single-seeded portions or ,two of which are seen in the figure, and the style appears to aiise from the baseof the carpels. Fio. 299.—Flower of Fennel (Fccniculum vujgare), one of the Umbclliferffl, cutvertically, Ehowing the fruit /, composed of two single-seeded cai-pols, orachenes, united, so as to form a cremocarp. The pendulous seeds are soen inthe carpels or mericarps. The two styles are seen at the apex of the fniit, withtheir dilated bases formed b
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