CONIFERALES (TAXACEAE) 



343 



much liigher number than among the podocarjjs. The suggestion 

 of a genetic connection between these two tribes will be considered 

 later. 



The course of spermatogenesis in the podocarps, from the division 

 of the generative cell just before fertilization, presents no unusual 

 features. In Dacrydhim (136) it was observed that the generative 



Fig. 398. — Phyllocladus alpina: apex of nucellus broken down by numerous pollen 

 tubes; the top of the endosperm also somewhat disorganized; each archegonium is 

 surrounded by a definite jacket; X180. — After Miss Kildahl (144). 



cell divides anticlinally, the stalk and body cells being side by side 

 and for some time indistinguishable. Presently one of them enlarges, 

 rounds off, and becomes free, while the nucleus of the other becomes 

 free by the disappearance of its wall or membrane. In the two genera 

 in which the male cells have been observed, the two extremes of varia- 

 tion are represented. In Phyllocladus (174) the body cell divides to 

 form two unequal male cells, only one of which functions (tig. 397) ; 



