lo Forms of Trees. [zoe 



the moist, snowless climate of the Pacific Coast north of San Fran- 

 cisco. 



B. The upright form with erect or horizontal branches. The 

 upright trunk in this form must be considered as inherited from an- 

 cestors where it was a necessity. Later on the sloping branches 

 gradually assumed a horizontal position. Example: most species 

 of cypress, yew, juniper, etc., of a more southern origin. It is 

 interesting to note the form of Cedrus Deodara or Himalaya cedar. 

 This tree, growing in regions of Himalaya where heavy snowfalls 

 are not unfrequent, possesses while young characteristically down- 

 ward sloping branches. Cednis Libani, Lebanon cedar, which is 

 only a form of C. Deodara, possesses no such sloping branches, but 

 horizontal branches, evidently developed in a climate where the 

 absence of heavy snow has made the downward slope of the 

 branches unnecessary. Most species of juniper possess erect 

 branches, as would be expected in a genus which finds its most con- 

 genial home and greatest development in the warmer regions of 

 the Mediterranean where snow is almost unknown. 



One species ( yiuiiperiis communis), however, which is common in 

 Northern Europe, is distinguished by a very different form from the 

 southern species, being dwarfed, prostrate, and repeatedly branched. 

 But that this form of the European juniper is not the natural 

 one, can be seen by the fact that whenever this species is transferred 

 to snowless localities it at once assumes the upright -form, growing 

 as straight and slender as a southern cypress. Similarly we find 

 this upright form possessed by all specimens of this juniper which 

 grow in close proximity to smelting works, where the heat is strong 

 enough to melt the snow. The different appearance oi this juniper 

 in such localities is really most startling. 



Pines which inhabit snow-visited regions are as a rule very up- 

 right, with downward sloping branches, while the southern pines, 

 both in Europe and North America, as well as in Central America and 

 Mexico, have branches which either spread horizontally or which 

 stand erect. Compare, for instance, /*. Lambcrtia7ia2>.nA P. Cembra, 

 which inhabit snow-visited regions, with such species as Aleppo 

 pine (P. Halapensis), P. maritima, P. insigiiis, and P. Sabiniana. 

 Judging by the forms of most species of pines it would seem as if 

 this genus is more of a southern origin, than for instance the various 

 genera of firs and spruces, which through their ver}-^ characteristic 



