THE INFLUENCE OF ENVIRONMENT ON PLANTS 



A, Campanula from 8,300 feet altitude at the left and one from 14,100 

 feet at right. B, from left to right, gentians growing in shade and 

 sunlight at 8,300 feet altitude, and alpine form from 13,000 feet. C, at 

 the left, alpine form, at the center, sunlight, and at the right, shade 

 forms of Androsace. From ''Plant Indicators." 



Courtesy of Doctor F. E. Clements and the Carnegie Institution. 

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