102 



GYMNOSPERMS 



nucleus passes to the growing tip; the- generative cell divides 

 to form a stalk cell and an antheridial cell; the antheridial 



FIG. 58. White pine. Five figures showing the entire strobilus, a longi- 

 tudinal section and a cross-section of the strobilus and scales with ovules. 



cells divides to form two non-ciliated sperms. The pollen 

 tube finally grows through the nucellus and the neck cells 

 of the archegonia and enters the venter. 



