. Botany for high schools and colleges. Botany. 402 BOTANY. wliich multiply by fission, and eventually unite into a con- tinuous tissue (in reality a false tissue), the endosperm {en, Fig. 297, B). In this mass of endosperm cells several near the micropylar end grow larger than the surrounding ones, and become filled with granular protoplasm. These are the corpuscula of Brown, the arcliegonia of Sachs, or the secondary embryo sacs of Henfrey [cp, cp, Fig. 297, B). In some cases they are placed singly at short distances from each other, while in others they are clustered together (1 and 2, Fig.
. Botany for high schools and colleges. Botany. 402 BOTANY. wliich multiply by fission, and eventually unite into a con- tinuous tissue (in reality a false tissue), the endosperm {en, Fig. 297, B). In this mass of endosperm cells several near the micropylar end grow larger than the surrounding ones, and become filled with granular protoplasm. These are the corpuscula of Brown, the arcliegonia of Sachs, or the secondary embryo sacs of Henfrey [cp, cp, Fig. 297, B). In some cases they are placed singly at short distances from each other, while in others they are clustered together (1 and 2, Fig. 298). Each corpusculum is at first a single cell, but when fully developed it consists of an elongated cell, the germ- cell proper, and, in many cases at least, one or more neck-cells, the whole sunk- en deeply into the sub- Fig. 298—1. Three corpnecula. cp, of Juni- staUCC of the Cndospcrm. penis communis, close together, and seen in a ,-p,, ^ • d -\ i n longitudinal section of the ovule ; ei, the first 1 hC nCCK IS lOrmed by the suspeneor cells of two fertilized corpuscula— , , • «> ^ _e at the upper end of the corpuscula are chown Cutting Ott 01 a portion 01 the neck cells ; p, the lower end of the pollen ;-| nvio-inal n^ll nf ihc^ nr>v tuhe. 2. A similar section taken a little later; tUC Ollgmal Celi 01 tnc COr- v,v,the suspensors, or pro-emhryos; e, e, e, ^^iTooi^him • in qatyip pricspq cells of the endosperm. 3. Lower end of sus- PUSCUiUm , in SOme CaSCS pensor, with enibryo.^6, begiiiningto develop, it remains sinde, whilc in 4, Longitudinal section ol the body or "nu- . . cleus," &A:, of the ovule, shown in outline; e, othcrS it dividcS SO aS to endosperm in enlarged embryo sac ; ^^ portion „ j_- i ^ of endosperm broken up: cp. three corpus- lOmi a VCrtlCal rOW, and cula, from the lower ends of which the suspen- • ,^ » sors, V, grow ; j), pollen tube. 1 and 2 X 200 ; m OtnCrS a lOUr- Or CVCn 3 X 100 ; 4 X Hofmeister ^-^
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