272 



COMMON TREES AND SHRUBS 



Examine the old fallen needles, and determine the 

 structures which are thrown off. It is the dwarf shoots 

 that fall and not merely the needle-leaves. 



Examine an old branch and note that the bases of the 

 scale-leaves of the long shoots persist and harden, and so 

 produce the roughness of the branch. 



Fig. 182. Scots Pine. 1, dwarf shoot; 2, elongated shoot 

 bearing scale-leaves with dwarf shoots in their axils : female cone 

 near end of branch ; 3, male cone ; 4, a single staminate branch ; 

 5, pollen-grain ; 6, branch bearing young female cone ; 7, ovule- 

 bearing scale ; 8, winged Pine-seed ; 9, old female cone ; a, stamens ; 

 ds, dwarf shoots ; /, foliage-leaf ; m, micropyle ; o, ovule ; po, 

 pollen-sac ; s.b, staminate branch ; sc, scale-leaves ; w, wing. 



The ' flowers ' of the pine are in cones and differ in 

 several important respects from typical flowers. The seeds 

 are not developed in the same cones as the stamens, but 

 arise on different branches of the same tree (monoecious). 

 The male cone (Fig. 182, 3) arises at the end of a branch, 

 and consists of a central axis which bears a tuft of dwarf 

 shoots at the tip. Below, and in the axils of the scale- 



