126 BOTANICAL GAZETTE [august 



rangia entirely cover the basal two-thirds of the abaxial surface {fig. 

 14). They are not arranged in sori and cover the basal and apical 

 sporophylls as completely as they do those in the middle of the cone. 

 The sporangium dehisces by a long slit which extends almost to its 



base. The microspores are s 

 and a quite prominent intine. 



moderately 



MALE GAMETOPHYTE AND SPERMS 



■ 



None of the pollen collected could be made to germinate, possibly 

 due to its age and to the fact that a fungus was growing in the material 

 when collected. 



In the earliest stages shown by the material, the male gametophyte 

 is already w^ell developed {fig. if). After the microspore reaches the 

 pollen chamber, the pollen tube grows upward and outward into the 

 nucellus. The relation of this growth in time to the development of 

 the structures within the tube could not be determined. In pollen 

 tubes at this stage there are usually a tube nucleus, a prothallial cell, 

 a stalk cell, and eight body cells {figs, ij, 18), The tube nucleus is 

 usually near the tip of the tube {figs. 18, ig), but sometimes behind 

 some of the body cells {fig. 13). Most of the body cells remain near 

 the base of the pollen tube, though some are usually near its tip. 

 While the number of body cells is most frequently eight, it varies to 

 nine {fig. 20), ten {fig. ig)^ and possibly more. Several illustrations 

 of such variation were found. 



The prothallial cell extends into the stalk cell {figs. 17-20) ^ as 

 described by Webber (6) in Zamia. At the base of the prothallial 

 cell there may be seen sometimes a darkly staining mass which may 

 possibly be the remnant of a first prothallial cell {figs. iQj 20). 



In the youngest body cell observed the two blepharoplasts are well 

 organized, each w4th numerous radiating lines of cytoplasm which 

 extend well down toward the equator of the cell {fig, 21). The 

 nucleus is sometimes irregular in form, as if its membrane in places 

 .were being pushed inward by the cytoplasmic radiations. When the 

 nucleus varies from the spherical form, it is more or less flattened at 

 right angles to the lines of radiating cytoplasm {figs. 17-20, 21, 47)* 

 At this stage the blepharoplasts are usually opposite each other, 

 and the entire cell presents a beautiful symmetrically arranged sphen- 



