Lectures on the physiology of plants . description of the reproductiveorgans. In Fig. 441 A is represented a flowerin its natural size; in B the floral envelopesand the nine stamens are cut away, and thewhole female reproductive apparatus consistingof six single separated carpels is representedslightly magnified. Each carpel bears abovea narrow process, the so-called Style, which inits turn bears at the upper end a brush ofhairs, the S/igma n; this has the function of holding fast the pollen-grainswhich have been carried to it from the opened anthers, in order that they maygerminate there, and
Lectures on the physiology of plants . description of the reproductiveorgans. In Fig. 441 A is represented a flowerin its natural size; in B the floral envelopesand the nine stamens are cut away, and thewhole female reproductive apparatus consistingof six single separated carpels is representedslightly magnified. Each carpel bears abovea narrow process, the so-called Style, which inits turn bears at the upper end a brush ofhairs, the S/igma n; this has the function of holding fast the pollen-grainswhich have been carried to it from the opened anthers, in order that they maygerminate there, and put forth their pollen-tubes first in the tissue of the styleand then in the cavity of the ovary. It is easier in the case of Bidomus than in many other plants to perceive that thecarpel together with its style and stigma constitute practically a leaf with the marginsfolded together longitudinally: this is obvious in Fig. 441 C, which representsthree carpels in transverse section. In other cases it is of course not so obvious, though. KiG. 440. — Pir-cone of Abies pcctinata (afterSchacht). A a leaf separated from tlie female floralaxis and looked at from above : it bears the ovuliferousscale s with the ovules sk (magnified). B upper partof the female flower (cone) m the mature state, j/axisof the cone (floral axis) ; c its leaves ; s the much-enlarged seminiferous scales. C a ripe seminiferousscale s with the two seeds sa and their wings f(reduced). FLOWERS OF ANGIOSPERMS. 759 the pods of the Bean, Pea, Bladder-Senna {Co/u/ca) and Paeony present easily observedcases of the same kind. The foliar nature of the ovary is somewhat more difficult todecipher when (as is in fact the commonest case) two, three, or more carpels areunited to form a simple two or more celled ovary. Suppose the three carpels repre-sented in C united inwards with one another and with the three which are absent, bytheir infolded margins: we should then have a six-celled ovary, consisting of sixcarpels. Con
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectplantph, bookyear1887
