PICEA EXCELSA AND RUBRA 115 



even after an endurance of the late severe May frost 

 of 191 5, and the unusually long visitation of cold 

 late winter winds of 1916 and 1917- 



GROUP II 

 P. ExcELSA, Rubra, Nigra, Alba, Albertiana 



Whilst towering firs in conic forms arise, 

 And with a pointed spear divide the skies. 



M. Prior. 



The primary instinct of an uninstructed mind would 

 in all probability regard the Common Spruce (P. 

 Excelsa) as the representative type of what all 

 properly conducted Spruces should and ought to be. 

 Possibly, if his inclinations carried him a little 

 farther on the paths of investigation, he would notice 

 that the leaves of some of these similarities were a 

 little longer than others, and also that perhaps a 

 different hue of colour here and there was apparent, 

 and one or two little minor differences of this sort. 

 But, on the whole, he would concur that the majority 

 of Spruces, although labelled by the doctrinaires with 

 different names, partook of a sufficient resemblance 

 to the Common Spruce to justify him in including 

 them mentally in one self-same category. If he went 

 a little farther still upon his journey of investigations, 

 the chances are he would soon be induced to modify 

 his opinions. 



Let us suppose that he came across a Picea Rubra, 

 he would at once notice a certain resemblance that 

 it bore to the Common Spruce. He would perceive 

 that the leaves of the P. Rubra were, on the whole, 

 shorter than those of the P. Excelsa. While the 

 Picea Rubra's leaves reach about half an inch in 

 length, those of the Excelsa average about twice 

 the length. Yet a young and weakly Common 

 Spruce can often be found with leaves as short. The 

 colour, too, is the same, we might almost say precisely 

 the same. So far we have not got much forwarder » 

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