THE 



167 



spring, and look carefully for the fertile and sterile 

 aments, which will usually be found on different 

 branches of the same tree. And, while you are 

 searching for their flowers, observe also their re- 

 markable foliage. Fig. 315 shows a fascicle of nee- 

 dle leaves from the pine. Observe the number of 

 leaves in each fascicle of the specimen 

 you are studying, for the species vary 

 in this respect. Fig. 316 represents the 

 scale-shaped leaves of arbor-vitse. In 

 evergreens of this sort observe the dif- 

 ference between the foliage on the older 

 and newer parts of the plant. In dioe- 

 cious species, observe whether the foli- 



FIG. 815. 



FIG. 816. 



age is of the same kind on both <$ and ? plants. 

 When you find awl-shaped leaves upon a young 

 branch, observe them from time to time, and note 

 their gradual passage into scale-shaped, imbricate 

 leaves. Do evergreens shed their foliage ? If so, 



