Text-book of botany, morphological and physiological . be; the pollen-cells of each pollen-sac remain united into a mass. ^ Compare with this Payers view (Organogenic de la fleur, p. 725), which differs in someessential points. ANGIOSPERMS, a^q The Gynoeceum is always the final structure of the flower. When the floralaxis has attained a suflicient length, the gynaeceum is formed at its apex; if the axisis flat, disc-like, or expanded, it stands in the centre of the flower; if it is hollowedout or cup-shaped, the gynaeceum is placed at the bottom of the hollow, in the centreof which lies the ap
Text-book of botany, morphological and physiological . be; the pollen-cells of each pollen-sac remain united into a mass. ^ Compare with this Payers view (Organogenic de la fleur, p. 725), which differs in someessential points. ANGIOSPERMS, a^q The Gynoeceum is always the final structure of the flower. When the floralaxis has attained a suflicient length, the gynaeceum is formed at its apex; if the axisis flat, disc-like, or expanded, it stands in the centre of the flower; if it is hollowedout or cup-shaped, the gynaeceum is placed at the bottom of the hollow, in the centreof which lies the apical point of the floral axis. In the diagram of the flower,Figs. 351 /, and 353 B, where each outer circle represents a lower transverse section,and each inner circle a higher one, the gynaeceum necessarily appears always asthe innermost central structure of the flower, the longitudinal displacements on thefloral axis being neglected in the construction of the diagram. When the axial part of the flower, the Receptacle or Torus, is so elevated in the. Fig. ^sx.—Fiitomus umbellatus: A flower (natural size); B the gynaeceum (magnified), the perianth and stamens removed,n the stigmas ; C horizontal section through three of the monocarpellary ovaries, each carpel bearing on its inside a number ofovules ; D a young ovule ; E an ovule immediately before fertilisation, ii the integuments, K the nucleus, KS the raphe, em theembryo-sac ; F horizontal section through the stigmatic portion of a carpel (strongly magnified), pollen-grains attached to thestigmatic hairs ; G horizontal section of a quadrilocular anther, but the valves z are so separated at ^ that it then appearsbilocular ; // part of an anther-lobe (corresponding to /3 in G), y the point where it has become detached from the connective,e the epidermis, x the fibrous layer of cells (endothecium); / diagram of the entire flower ; the perianth // consists of twoalternate whorls of three leaves, as also does the androecium, but
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
