144. A leaf mosaic of Norway maple. Note the 

 lengths of petioles. 



Shoot of the common white pine, one-third natural size. 



The PiPture shows the falling of the leaves from the different years 

 growth, rho part of the liranch between the tip and A is the last 

 season s growtli ; between A and B it is two years old ; the part 

 Detween B and C is three years old; it has few leaves. The part that 

 grew four seasons ago— beyond C— has no leaves. 



