326 OUR NATIONAL PARKS 



the northward, forty miles wide, between the 

 Stanislaus and Tuolumne groves, occurs in the 

 channel of the great Stanislaus and Tuolumne 

 glacier, and that the smaller gap between the 

 Merced and Mariposa groves occurs in the chan- 

 nel of the smaller Merced glacier. The wider 

 the ancient glacier, the wider the gap in the 

 Sequoia belt, while the groves and forests attain 

 their greatest development in the Kaweah and 

 Tule Elver basins, just where, owing to topo- 

 graphical conditions, the region was first cleared 

 and warmed, while protected from the main ice- 

 rivers, that flowed past to right and left down 

 the Kings and Kern valleys. In general, where 

 the ground on the belt was first cleared of ice, 

 there the Sequoia now is, and where at the same 

 elevation and time the ancient glaciers lingered, 

 there the Sequoia is not. What the other condi- 

 tions may have been which enabled the Sequoia 

 to establish itself upon these oldest and warm- 

 est parts of the main soil-belt I cannot say. I 

 might venture to state, however, that since the 

 Sequoia forests present a more and more ancient 

 and long established aspect to the southward, the 

 species was probably distributed from the south 

 toward the close of the glacial period, before the 

 arrival of other trees. About this branch of the 

 question, however, there is at present much fog, 

 but the general relationship we have pointed out 

 between the distribution of the Big Tree and the 



