Elementary botany . Fig. division of the egg in the at once organize the nuclear figure for the whit? pif cutting off the ventral canal cell at the apex of the first division of the thus formed, and these dfour nuclei which sink to the bottom of the archegonium and there organ- Two nuclei archegonium. End, endospermare thus formed, and these divide to form ArB* arche^onium 5o8 MORPHOLOGY. ize the embryo which pushes its way into the endosperm from which itderives its food (fig. 362). 626. Homology of the parts of the female cone.—Opinions are divided asto the homology of th
Elementary botany . Fig. division of the egg in the at once organize the nuclear figure for the whit? pif cutting off the ventral canal cell at the apex of the first division of the thus formed, and these dfour nuclei which sink to the bottom of the archegonium and there organ- Two nuclei archegonium. End, endospermare thus formed, and these divide to form ArB* arche^onium 5o8 MORPHOLOGY. ize the embryo which pushes its way into the endosperm from which itderives its food (fig. 362). 626. Homology of the parts of the female cone.—Opinions are divided asto the homology of the parts of the female cone of the pine. Some considerthe entire cone to be homologous with a flower of the angiosperms. The. Fig. of white pine at stage of fertilization, en, egg nucleus; spn, spermnucleus in conjugation with it; nb, nutritive bodies in cytoplasm of large egg;cpt, cavity of pollen tube; vn, vegetative nucleus or tube nucleus; sc, stalk cell:spn, second sperm nucleus: pr, portion of prothallium or endosperm; sg, starchgrains in pollen tube. The sheath of jacket cells of the archegonium is not shown.(After Ferguson.) entire scale according to this view is a carpel, or sporophyll, which is dividedinto the cover scale and the ovuliferous scale. This division of the sporo-phyll is considered similar to that which we have in isoetes, where the spo-rophyll has a ligule above the sporangium, or as in ophioglossum, where theleaf is divided into a fertile and a sterile portion. Others believe that the ovuliferous scale is composed of two leaves situ-ated laterally and consolidated representing a shoot in the axis of the is some support for this in the fact that in certain
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Keywords: ., bookauthoratk, bookcentury1900, bookdecade1900, booksubjectbotany
