Transactions of the Canadian Institute. [Vol. VII. 



(2). The general effect of placing the plant under a bell jar is to 

 retard growth of stem but promote growth of leaves. 



(3). Plants deprived of all food matter, except that contained in the 

 air and in pure water, will grow rather rapidly for a time but will 

 gradually die, the leaves first turning yellow. 



(4). Plants grown in a moist atmosphere tend to send out roots at 

 the internodes as well as at the nodes. 



(5). A nutrient solution fed in the form of a spray to a plant seems 

 to affect the plant in a way similar to that of a nutrient solution applied 

 to the roots, as in the ordinary water culture, and therefore it may be 

 assumed that some, at least, of the solution had been absorbed* and had 

 been used in the general vital processes of the plant. Though the plant, 

 fed with a solution applied to the leaves in the form of a spray, did not 

 show a healthy or vigourous growth, yet the same may be said of the 

 plant whose roots were supplied with the solution. 



On the completion of the experiments, January 7th, the liquid 

 medium in which the roots dipped was examined, and it was found that 

 in the case of i and 2, none of the liquid spray had made its way down 

 into the water about the roots. The liquid, however, showed an acid 

 reaction in all cases. It was found further that those plants growing in 

 distilled water, 7 and 8, had a much more extensive growth of roots 

 than 5 and 6, those in the nutrient solution. 



Series III. 



The following series of experiments was arranged and conducted in 

 the basement of the University Museum where the atmosphere was 

 exceedingly dry at that season of the year, but the temperature was 

 fairly constant, ranging from 60 to 70 degrees F. The plants supplied 

 by a spray were arranged as shown in Fig. 7, while the others were 

 placed under bell jars with ventilators. These were aerated daily, as 

 were also the roots of the plants, and this aeration was accomplished by 

 forcing a stream of air into the liquid surrounding the roots. The 

 capacity of the bell jars was twenty-four liters. 



The number of leaves was recorded regular!)', and measurements 



■ Absorption by the leaves is indicated also by the experiments in Chapter X. 



