2l6 



Transactions of the Royal Canadian Institute 



The record on the drum was frequently checked by direct measure- 

 ment of the growing part. 



The environment. — The work was done at Carmel, California, at the 

 Coastal Laboratory of the Carnegie Institution of Washington, chiefly 

 during the summers of 1912 and 1916. Following is a brief exposition 

 of the environmental conditions. 



«^ 



per /lour 



7 



p ro 



rZ /3 /<• /^ // // /S ff ZC Zf 22 2 3 Z* 



Figure 3. r;' Average hour"rates of growth for fifty-three days. 



The outstanding feature of the summer climate is its monotony, and 

 it is this that makes physiological studies in the field particularly in- 

 structive. Day after day during the summer the cycles of temperature, 

 moisture and lighting repeat themselves with remarkable regularity. 

 The disturbances which do occur are due chiefly to the m.ovement of 



(^ya-/z, 



//»ur^ V / <S p fO fi f2 f^ fU // /6 // fS /^ 



Figure 4. Average hour rates of growth of seven internodes for the periods indicated (see protocol, 



p. 242). 



