. Morphology of spermatophytes. [Part I. Gymnosperms]. Gymnosperms; Plant morphology. CONIFBRALES 93 the stalk cell and body cell (Fig. 69, L). In tMs case tlie two cells, so far as we have observed or seen figured, are " fore and aft" with reference to each other, and not side by side, as in Cycads and Ginkgo, the stalk cell being nearer the old spore wall. It appears, therefore, that the generative cell per- sists for about eleven months without dividing. The pollen tube branches as it traverses the nucellus, not so extensively as do the tubes of Cycads and Ginkgo, but sufficiently
. Morphology of spermatophytes. [Part I. Gymnosperms]. Gymnosperms; Plant morphology. CONIFBRALES 93 the stalk cell and body cell (Fig. 69, L). In tMs case tlie two cells, so far as we have observed or seen figured, are " fore and aft" with reference to each other, and not side by side, as in Cycads and Ginkgo, the stalk cell being nearer the old spore wall. It appears, therefore, that the generative cell per- sists for about eleven months without dividing. The pollen tube branches as it traverses the nucellus, not so extensively as do the tubes of Cycads and Ginkgo, but sufficiently to give evi- dence of its primitive service as an absorbing or rhizoidal organ. It consumes about two months in traversing the nucellus after its second start, entering the archegonium about the 1st of July. The liberation and descent of the body cell into the tube, accompanied by the freed nucleus of the stalk cell whose wall has been ruptured, and their association with the tube nucleus near the tip of the tube, has been described in detail by Dixon for Pinus silvestris, and his account applies as well to Finns Laricio, except that we find no definite order of arrange- ment in the relative posi- tions of these three bodies. Just before fertilization, about two months after the division of the generative -cell into stalk and body cells, the latter divides and forms the two male cells (mor- phologically sperm mother â cells). It is this division which in the Cycads is ac- â¢companied by the appear- ance of blepharoplasts, and results in the organization â¢of two ciliated male cells. So far as observed, however, bleph- aroplasts do not appear in Conifers and the male cells do not become ciliated. This is doubtless associated with the fact that in Conifers the pollen tube has become a sperm carrier, while in the Cycads it performs no such function. At the time of fer- tilization, besides dense cytoplasm rich in starch, the tip of the pollen tube contains four bodies, namely
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