13 



the apical one have taken the form of small cones of pinkish scales 

 (the female flowers), each scale having two ovules (immature seeds) 

 at their base. These cones are at first erect, with the scales some- 

 what spread, and therefore ready to catch the pollen as it is carried 

 hither and thither by the wind (PI. IV, fig. i). 



Pollination being effected, the erect position is no longer advan- 

 tageous, and the cones turn over (PI. IV, fig. 2). Within the cones 

 the pollen grains extrude their tubes as usual, which will convey 

 the fertilizing atoms of protoplasm to the egg-cells of the female 

 flowers. The growth is slow, however, and the tubes will not reach 

 the eggs and bring about fertilization till the spring of 1910, and 

 meanwhile the cones will increase but little in size. During the year 

 1910 the green cones will grow rapidly (PI. V, fig. i), and by the 

 spring of 191 1 will be full-grown and brown, the seeds being full- 

 grown also. Then in March or April of that year the scales of which 

 the cone is composed will spread open with a crackling sound (PI. 

 V, fig. 2). The seeds will be set free, to be whirled away by means 

 of their wings to spread the fir-wood on such poor soil as will produce 

 but little besides. 



