THE FORESTS 197 



valley and down the Sierra from the north ; conse 

 quently, when the Sierra soil-beds were first thrown 

 open to preemption on the melting of the ice-sheet, 

 the Sequoia may have established itself along the 

 available portions of the south half of the range 

 prior to the arrival of the Sugar Pine, while the 

 Sugar Pine took possession of the north half prior 

 to the arrival of Sequoia. 



But however much uncertainty may attach to this 

 branch of the question, there are no obscuring 

 shadows upon the grand general relationship we 

 have pointed out between the present distribution 

 of Sequoia and the ancient glaciers of the Sierra. 

 And when we bear in mind that all the present for 

 ests of the Sierra are young, growing on moraine 

 soil recently deposited, and that the flank of the 

 range itself, with all its landscapes, is new-born, re 

 cently sculptured, and brought to the light of day 

 from beneath the ice mantle of the glacial winter, 

 then a thousand lawless mysteries disappear, and 

 broad harmonies take their places. 



But although all the observed phenomena bearing 

 on the post-glacial history of this colossal tree point 

 to the conclusion that it never was more widely 

 distributed on the Sierra since the close of the 

 glacial epoch ; that its present forests are scarcely 

 past prime, if, indeed, they have reached prime; 

 that the post-glacial day of the species is probably 

 not half done ; yet, when from a wider outlook the 

 vast antiquity of the genus is considered, and its an 

 cient richness in species and individuals ; compar 

 ing our Sierra Giant and Sequoia sempervirens of 

 the Coast Range, the only other living species of Se- 



