CHAPTER XII. 



SCOTS PINE, YEW, CYCAS. 

 SCOTS PINE (PINUS SILVESTRIS). 



514. General External Characters. In studying 

 the Scots Pine, at different times of year, note the following 

 general features : 



(1) The "excurrent" habit, the long straight trunk 

 passing right to the top of the tree and tapering out. 



(2) The scaly bark, orange-coloured except at the base of 

 the trunk, where it is darker, and the rough scaly surface 

 of the younger bare twigs. 



(3) The origin of the branches, in apparent whorls, from 

 lateral buds, each of which arises in the axil of a scale-leaf 

 at the end of each year's growth. 



(4) The consequent indication of the age of the tree by 

 the number of these apparent whorls even in the lower 

 portion the stumps of fallen branches may be seen in 

 whorls. 



(5) The spiral arrangement of the scale-leaves on the 

 twigs, showing that the branching is not in reality 

 whorled. 



(6) The appearance of a tree in which the main axis 

 happens to have been injured a lateral branch bends 

 upwards and replaces it, forming a new "leader" and often 

 giving the top of the tree a bayonet shape. 



(7) The short shoots (" dwarf shoots," or " foliar spurs," 

 or " shoots of limited growth "), each arising in the axil of 

 one of the brown scale-leaves borne on either the main 

 stem or one of the ordinary branches ("long shoots" or 

 " shoots of unlimited growth "). 



(8) The narrow twisted green foliage-leaves ("needles"), 

 two borne on each dwarf -shoot or "bifoliar spur." 



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