106 



EXPERIMENT STATION RECORD. 



plants in white and red light under the same temperature and the 

 same intensity of light. The same temperature was obtained in the 

 different houses by means of screens of loosely woven white linen, which 

 allowed only a limited passage of the sun's rays but which did not 

 alter the quality of the rays. The subjects of the experiments were sen- 

 sitive plants, maize, peas, beans, lettuce, strawberries, fig-trees, Achy- 

 rantha, Perilla, Coleus, Strobilanthes, Tradescantia, grapes, etc. Some 

 of the most interesting results are appended. On June 13 three pots of 

 equally vigorous sensitive plants, 0.03 meter in height, were placed in 

 each hothouse. Their increase in height at different dates is shown 

 in the following table: 



The sensitive plant in the red hothouse attained a greater height and 



was more sensitive 

 than that in the 

 white hothouse, 

 and its vegetative 

 development was 

 more advanced. 

 It began to bloom 

 October 1, while the 

 plant in the white 

 hothouse began 

 October 12. The 

 sensitive plant in 

 the green hothouse 

 remained almost at 

 a standstill, became 

 etiolated and, the 

 nutrition becoming 

 insufficient, the 

 plant ceased to 

 grow. The plants 

 in the white hot- 

 house, grown under 

 the same condi- 



FlQ. 3.— Sensitive plants growji at the same temperature in different . . n + r . Tnnar , m 



colored light, tions ot teinpera- 



tirre, moisture, and 

 illumination as those of the red hothouse, attained a height of only 



RED 



WHITE GREEN BLUE 



