Text-book of botany, morphological and physiological . aves, are arranged in alternating whorls. But, occasionally, as in Taxus,greater differences are to be observed in the phyllotaxis of the flowering shoot ascompared with that of the foliage-shoots. The Male Flowers always consist of a distinctly elongated axis provided withstaminal leaves, and ending above in a naked apex (Fig. 319 ^). The stamens aremostly more delicate and of a different colour from the foliage-leaves, and are usuallydivided into a slender pedicel and a peltate lamina bearing the pollen-sacs on itsunder side, as in Taxus
Text-book of botany, morphological and physiological . aves, are arranged in alternating whorls. But, occasionally, as in Taxus,greater differences are to be observed in the phyllotaxis of the flowering shoot ascompared with that of the foliage-shoots. The Male Flowers always consist of a distinctly elongated axis provided withstaminal leaves, and ending above in a naked apex (Fig. 319 ^). The stamens aremostly more delicate and of a different colour from the foliage-leaves, and are usuallydivided into a slender pedicel and a peltate lamina bearing the pollen-sacs on itsunder side, as in Taxus, the Cupressineae, and Abietinese (Fig. 318^, 319^,^,320 A). The flat expansion at the end of the pedicel may, however, be entirelyabsent, as in Salisburia (Fig. 317 C), where it is reduced to a small knob on whichthe pollen-sacs hang. That the parts which bear the pollen-sacs in Coniferae arebeyond doubt metamorphosed leaves, is evident not only from their form, but stillmore from their arrangement, which has already been spoken of. If the staminal. Fig. -^fio.—Abiespectinata ; A a male flower, b the delicate bud-scales forming a perianth, a the stamens ; B a pollen-g-rain(after Schacht), e its extine, forming the two large vesicular protrusions bl. leaves of the Cycade;^ show a resemblance in more than habit to the sporangiferousleaves of Ferns, those of Coniferse may perhaps be compared to the parts thatbear the sporangia of Equisetacese ; and not unfrequently, as in Taxus, Juniperus,&c., the resemblance of the male flowers to the inflorescence of Equisetum is asstriking in external appearance as in the actual agreement between them from amorphological point of view. The pollen-sacs, of the structure and developmentof which but little is at present known, usually hang, with a narrow base, on theunder side of their support, and do not cohere in their growth; their number isusually much smaller than in Cycadeae, but much more variable than in Angio-sperms ; in the yew the p
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectbotany, bookyear1875
