19 BOTANY. 



of the scales, just as they are beginning to spread, or before the 



Fig. 165. Fig. 166. Fig. 167. Fig. 168. Fig. 169. 



Sterile seal e. Scale with Seeds have Back of scale Winged 

 Seeds undevel- w e 1 1 ^ developed split off from with small cover se~ed free 

 oped. seeds. scale. scale. from scale. 



Figures 165-169 White pine showing details of mature scales and seed. 



seeds have scattered, we shall find the seeds attached to the 

 upper surface at the lower end. There are two 

 seeds on each scale, one at each lower angle. 

 They are ovate in outline, and shaped some- 

 what like a biconvex lens. At this time the 

 seeds easily fall away, and may be freed by 

 jarring the cone. As the seed is detached from 

 the scale a strip of tissue from the latter is 

 peeled off. This forms a "wing" for the 

 seed. It is attached to one end and is shaped 

 something like a knife blade. On the back of 

 the scale is a small appendage known as the 

 cover scale. 



312. Formation of the female pine cone. 

 The female flowers begin their development 

 rather late in the spring of the year. They 

 are formed from terminal buds of the higher 

 branches of the tree. In this way the cone may 

 terminate the main shoot of a branch, or of 

 the lateral shoots in a whorl. After growth 

 Female cones of the has proceeded for some time in the spring, 



pine at time of pollina- 

 tion, about natural size. t he terminal portion begins to assume the ap- 



Fig. 170. 



