Text-book of botany, morphological and physiological . \ The flower consists of a strong conical elongated axis, * The hypothesis that the male flower of Cycas Rutnphii is one, the leaf-bud by which the stemis prolonged the other bifurcation of the dichotomising apex of the stem, is not supported byDe Barys recent researches. CFCADEM. 439 sometimes supported on a naked peduncle, but densely covered in other parts by alarge number of staminal and carpellary leaves arranged spirally. In Cycas the female flower is a rosette of foliage-leaves which have under-gone but slight metamorphosis (Fig. 31
Text-book of botany, morphological and physiological . \ The flower consists of a strong conical elongated axis, * The hypothesis that the male flower of Cycas Rutnphii is one, the leaf-bud by which the stemis prolonged the other bifurcation of the dichotomising apex of the stem, is not supported byDe Barys recent researches. CFCADEM. 439 sometimes supported on a naked peduncle, but densely covered in other parts by alarge number of staminal and carpellary leaves arranged spirally. In Cycas the female flower is a rosette of foliage-leaves which have under-gone but slight metamorphosis (Fig. 314), the apex of the stem developing againfirst of all scale-leaves, and then new whorls of foliage-leaves; the stem, therefore,grows through the female flower, or furnishes an instance of prolification. Theseparate carpels are, indeed, much smaller than the ordinary foliage-leaves, but areessentially of the same structure; the lower pinnae are replaced by ovules, whichattain, even before fertilisation, the magnitude of a moderate-sized ripe plum, the. Fig. 31s—^amia muricata (after Karsten). A a male flower {natural size); B transverse section of one; C oneof its stamens with the pollen-sacs x and the peltate expansion s (seen from below); D the upper part of a femaleflower (natural size); E transverse section of one, s the peltate placenta of the ovules sk; F longitudinal section ofa ripe seed ; e endosperm, c cotyledons, x the folded suspensor. fertilised seed acquiring the dimensions and the appearance of a moderate-sizedripe apple, and hanging quite naked on the carpel. Whether the male flower ofCycas also exhibits prolificalion I do not know, and it seems improbable; the verynumerous staminal leaves are much smaller, 7 to 8 cm. long, and undivided; theyexpand considerably from a narrow base and terminate in an apiculus. They arefurnished on the under side with a number of densely-crowded pollen-sacs; thewhole flower is from 30 to 40 cm. long. The male and female flowers
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
