. Botany for high schools and colleges. Botany. 403 BOTANT. tvhich multiply by fission, and eventually unite into a con- tinuous tissue (in reality a false tissue), the endosperm {en, Fig. 397, 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 corpiiscula of Brown, the a7'chegonia of Sachs, or the secondary embryo sacs of Henfrey {cp, cp, Pig. 397, 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. 403 BOTANT. tvhich multiply by fission, and eventually unite into a con- tinuous tissue (in reality a false tissue), the endosperm {en, Fig. 397, 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 corpiiscula of Brown, the a7'chegonia of Sachs, or the secondary embryo sacs of Henfrey {cp, cp, Pig. 397, 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. 398). Each corpusculum is at first a single cell, but when fully developed it consists of an elongated cell, the germ- cell proper, and, in ma-ny cases at least, one or more neck-cells, the whole sunk- en deeply into the sub- Fig. 298—1. Three corpuecula. f7), oi Jurti- stance of the endospcrm. perus commwm^ close together, and seen in a r„- i • , », the suspensors, or pro-embryos; e, e, e, nnafnliiTn • in omno nnspu cells of the endosperm. 3. Lowe? end of BUS- P^^®'^'^^'^'"' ^^ ®"™® ^^^^ pensor, with enibryo.«6, beginning to develop, it remains single, while in 4, Longitudinal section ol the body or "nu- . .*^ ' cleuB,"**, of the ovule, shown in outline; e, others it divides SO aS tO endosperm in enlarged embryo sac ; c', portion „ ,• i -i of endosperm broken up; ep. three corpus- lorm a Vertical rOW, and cula, from the lower ends of which the suspen- • ,^ « sors, V. grow; p, pollen tube. 1 and 2 X 300; m Others a lour- or even B X 100 ; 4 X Hofmeister. ^-^-^^ _ ^^^^^^ tranSVerse plane (see Pig. 398, 1) ; the latter arrangement has been termed a rosette. 511.—If we now review the structure of the ovule its ho- mologies can be readily made out. The ovule itself plainly •corresponds to the macrosporangium of the higher Pterido- phytes, and the embryo sac is to be regarded as the homo-. Please note that these images are e
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1888
