THJl DEFLECTED AXIS OF GJROWTff 



13 



befall the shoots above. Each of these four shoots 

 has two terminal buds, and each of the shoots is 

 unlike the other. 

 It is easy to see 

 that the shoot a 

 is to become the 

 head of the fam- 

 ily. Fig. 10 will 

 suggest investiga- 

 tion of the com- 

 mon black haw or 

 viburnum. Fig. 

 11 is a sumac 

 bush, with its zig- 

 zag and forking 

 growths ; and the 

 terminal clusters 

 of seeds explain 

 how the forking 

 has arisen. The 

 forks are most ap- 

 parent at the tips 

 of the branches ; 

 this only means 

 that many of ■ the older branches have perished ; or 

 perhaps the buds never developed on one side. 

 Irregular development among branches is the result 

 of struggle for existence. 



Fig. 11. 

 Tbe forking growth of a sumac bush. 



