192 



BOTANY. 



smaller end. These are the macrosporangia, or, as they are called 

 in the higher plants, the ovules. These ovules, as we see, are 

 in the positions of the seeds on the mature cones. In fact the 

 wall of the ovule forms the outer coat 

 of the seed, as we will later see. 



315. Pollination. — At the time when 

 the pollen is mature the female cones 

 are still erect on the branches, and the 

 scales, which during the earlier stages of 

 growth were closely pressed against one 

 another around the axis, are 

 now spread apart. As the 



Fig. 174. 



Branch of white pine showing young female cones at time of pollination on the ends of 



the branches, and one-year-old cones below, near the time of fertilization. 



clouds of pollen burst from the clusters of the male cones, 

 some of it is wafted by the wind to the female cones. It is here 

 caught in the open scales, and rolls down to their bases, where 

 some of it falls between these forceps-like processes at the lower 

 end of the ovule. At this time the ovule has exuded a drop of 



