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lk, or from the placenta when there is no seed-stalk. [Illustration: Fig. 418. Seed of White Water Lily, enclosed in its aril.] 384. A short and thickish appendage at or close to the hilum in certain seeds is called a CARUNCLE or STROPHIOLE (Fig. 419). [Illustration: Fig. 419. Seed of Ricinus or Castor oil plant, with caruncle.] 385. The various terms which define the position or direction of the ovule (erect, ascending, etc.) apply equally to the seed: so also the terms anatropous, orthotropous, campylotropous, etc., as already defined (320, 321), and such terms as HILUM, or _Scar_ left where the seed-stalk or funiculus falls away, or where the seed was attached directly to the placenta when there is no seed-stalk. RHAPHE, the line or ridge which runs from the hilum to the chalaza in anatropous and amphitropous seeds. CHALAZA, the place where the seed-coats and the kernel or nucleus are organically connected,--at the hilum in orthotropous and campylotropous seeds, at the extremity of the rhaphe or tip of the seed in other kinds. MICROPYLE, answering to the _Foramen_ or orifice of the ovule. Compare the accompanying figures and those of the ovules, Fig. 341-355. [Illustration: Fig. 420. Seed of a Violet (anatropous): _a_, hilum; _b_, rhaphe; _c_, chalaza.] [Illustration: Fig. 421. Seed of a Larkspur (also anatropous); the parts lettered as in the last.] [Illustration: Fig. 422. The same, cut through lengthwise: _a_, the hilum; _c_, chalaza; _d_, outer seed coat; _e_, inner seed-coat; _f_, the albumen; _g_, the minute embryo.] [Illustration: Fig. 423. Seed of a St. John's-wort, divided lengthwise; here the whole kernel is embryo.] 386. =The Kernel, or Nucleus=, is the whole body of the seed within the coats. In many seeds the kernel is all _Embryo_; in others a large part of it is the _Albumen_. For example, in Fig. 423, it is wholly embryo; in Fig. 422, all but the small speck (_g_) is albumen. 387. =The Albumen or Endosperm= of the seed is sufficiently characterized and its office explained in Sect. III., 31-35. 388. =The Embryo= or _Germ_, which is the rudimentary plantlet and the final result of blossoming, and its development in germination have been extensively illustrated in Sections II. and III. Its essential parts are the _Radicle_ and the _Cotyledons_. 389. =Its Radicle or Caulicle= (the former is the term long and generally used in botanical descriptions, but the latter is
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