. Morphology of gymnosperms. Gymnosperms; Plant morphology. 344 MORPHOLOGY OF GYMNOSPERMS while in Podocarpus (69) only the nucleus of the body cell is said to divide and all of the cytoplasm to be organized in connection with one of the male nuclei as a male cell, leaving the other male nucleus thrust out at its periphery. In Saxegothaea (149) pollen falls not only on the extruded and broadly flaring tip of the nucellus, but sometimes also in the depression around the o^nxle, and in this position pollen tubes develop and grow over the tissues to the micropyle. It will be remembered that this
. Morphology of gymnosperms. Gymnosperms; Plant morphology. 344 MORPHOLOGY OF GYMNOSPERMS while in Podocarpus (69) only the nucleus of the body cell is said to divide and all of the cytoplasm to be organized in connection with one of the male nuclei as a male cell, leaving the other male nucleus thrust out at its periphery. In Saxegothaea (149) pollen falls not only on the extruded and broadly flaring tip of the nucellus, but sometimes also in the depression around the o^nxle, and in this position pollen tubes develop and grow over the tissues to the micropyle. It will be remembered that this growth of pollen tubes to the micropyle from some distance outside is one of the features of the araucarians (p. 283). FERTILIZATION i\mong the Taxaceae the tip of the pollen tube discharges all of its free contents into the cytoplasm of the egg, in the peripheral region of which there may be found both male cells or nuclei, the stalk and tube nuclei, and such prothallial nuclei as may be in the tube. All of these gradually disappear except the functioning male cell or nucleus, although some- times they may still be distinguished in the early stages of the proembryo. In Cephalotaxus Foriunei the non-functioning male nucleus has been observed (55) to divide amitotically, producing as many as six nuclei. In Phyllocladus (174) the male cells are discharged outside the archegonium and pass between the separated neck cells. In Torreya calijornica (99), Torreya taxifolia (loi), Cephalo-. FiG. 399.—Torreya taxifolia: fertilization; the male nucleus is in contact with the egg nucleus; the cytoplasm of the male cell is closely applied to the egg nucleus; the functionless male cell and stalk and tube nuclei are in the upper part of the egg; August 12', 1904; X460.—^After Coxjlter and Land (ioi).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectl
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