PHYSICAL AND METEOROLOGICAL RESEARCHES. 



109 



The results with the Frankenthal were absolutely the same. There 

 was an extraordinary development of branches iu the red house, sur- 

 passing the white in this respect. This difference was greatly increased 

 by pinching off the branches. The plants in the green light soon 

 stopped growing and made only a few new leaves. The plants in the 

 blue house continued to grow slowly. To recapitulate: The vine in the 

 white house grew but slowly; its wood was well developed ; it remaiued 

 short and vigorous during the entire season. The vine in the red house 

 grew in length, but lost much in vigor; its numerous branches had fre- 

 quently to be pinched back, and its foliage was but little colored. The 

 vine in the blue house grew slowly, considering the rapid start made; 

 it remained vigorous with large dark-green leaves. One year-old vines 

 behaved in the same manner; the vines in the white hothouse were vig- 

 orous and developed a more luxuriant growth than those in the other 

 houses. In general, the phenomena in case of the grapes were similar 

 to those observed in the case of sensitive plants. However, the bine 

 rays were not so unfavorable to the development of the vine as they 

 were for other plants. The experiments with vines were concerned 

 only with the vegetative growth, and not with the fruiting. 



The development of Perilla was intense in the white and red houses, 

 the plants in the white surpassing in vigor those in the red. The plants 

 in the green house changed little during the experiments, while those 

 in the blue remained inactive. 



Experiments with Coleus showed little difference in growth. The 

 plant in the white hothouse spread and made a magnificent ornamental 

 plant. That in the red house, while showing less foliage, increased in 

 height. In the green and white houses there was very little develop- 

 ment. 



The results with Achy ran tha accord with those for the sensitive 

 plant. The plant in the red house grew so much in length that its 

 branches could hardly hold np. 



Three young potted strawberry plants of the same age and vigor 

 were placed in each hothouse in May. Iu June the plants fruited with 

 the following result: 



Effect of different colored liyht on fruiting of strawberries. 



In the open air — 

 In white hothouse 

 In red hothouse . . 

 In green hothouse 

 In blue hothouse . 



Only the plants in the white hothouse and those in the open air pro- 

 duced any considerable number of fruits. The plants receiving the 

 total radiation yielded five times as many fruits as those which grew 



