AUTONOMIC MOVEMENTS IN SUCCULENTS 



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continuous rise for both day and night, but a faster rate for the day than for the 

 night. Plant No. 4 was kept in constant darkness after irrigation and continued 

 to rise during the two days and nights. Its rate was slower than that of the 

 others, but the rates varied so much from plant to plant and from branch to 

 branch that it was impossible to tell what the rate of No. 4 might have been if it 

 had not been kept in darkness. 



Experiment 7. 



TABLE 6 



Movements under different conditions of evaporating 

 power of the air 



Experiment 7. 



Object: Measurement of movements under conditions of the high evaporation 

 existing in the open in the sun, with the tissues of the plant turgid and the soil 

 water content high. 



Material: Plants Nos. 1, 2, 8, 15, and 16. Plants 1 and 2 had spent their entire 

 life in the green-house, the others in the open. 



Method: All plants were measured at four-hour intervals, on the first day in 

 the green-house, on the second day in the open, under the influence of bright sun 

 and a high wind. On the third day the plants were again placed in the open, 

 but on this day the velocity of the wind was not so high. The plants were placed 

 in the green-house at night. 



Results: The movements are shown in table 6. Two of the three plants which 

 had grown in the open, Nos. 15, and 16, moved upward both in the green-house 



