THE CLUSTER PINE. 



Pi'nus Pinaster Ait. 



It appears tolerably certain that we have m the 

 Ahieti'nae the most highly specialised forms of 

 Conifers, and that, among the Ahietince, this pre- 

 eminence belongs to the genus Pi'nus. It is also 

 to be borne in mind that the two genera Pinus 

 and A'bies — rivalled, if at all, by their close allies 

 the Spruces (Pice'a), Larches (La'rix), and Hem- 

 locks (Tsu'ga) — by their immense multiplication of 

 individuals, often constituting " pure " forests of 

 single species, cover wider areas in .the Northern 

 Hemisphere than those occupied by any species of 

 tree in any quarter of the globe. 



The AhietincB are almost all of them lofty 

 trees, more or less pyramidal in outline, their 

 branches, which are given off approximately in 

 whorls, being generally of insignificant bulk as com- 

 pared with that of the main, trunk. Their stems 

 grow erect and straight to heights of a hundred to 

 two hundred feet, with a regularly tapering outline, 

 and sometimes become free of branches for more 

 than half their height from the ground. This arises 

 from the important character, preserited also by 

 the Sequoias, of the early decay and throwing 

 off of the side branches. Thus the branches, it 

 has been said, " in a physiological point of view, 

 may be considered as rather like immense leaves than 

 ^ 33 



