THE PLAINS AND COLORADO 119 



When we left Denver on June 12, it was sum- 

 mer. The trees were in full leaf, and many of 

 the early flowers of spring were faded and gone, 

 their places taken by the later comers that 

 decorated the summer landscape of the region. 

 Beginning to ascend the mountains as the first 

 foot-hills were attained, it was perceptible that 

 each hundred feet of elevation had put the clock 

 of nature backward. As the route passed over 

 some considerable altitude, at first the leaves on 

 the trees were only half developed ; higher up they 

 were just breaking the buds, and later, as the 

 highest point was reached, only the haze that in- 

 dicates the renewal of leaf and flower on the trees 

 was visible. Along with this backward turning 

 of the season one saw all the early spring flowers 

 in various stages of growth inversely from the 

 flowers to the bud about to blossom. There are 

 other phenomena connected with life and growth, 

 one of which I can suggest by a concrete example. 

 There was a kind of sunflower blooming on all the 

 foot-hills, and ordinarily the stock which carried 

 the golden disk, some five inches across, was any- 

 where from four to five feet high. Gradually 

 with the ascent of the backbone of the chain, the 

 height of the stalks of the sunflowers was in in- 

 verse ratio to the altitude of the hills. That is, 

 while the flower was five inches across in the 

 lower regions, and on a stalk some four or five 



