Transactions of the Canadian Institcte. 



[Vol. VII. 



conducted to determine whether similar substances could be extracted 

 from leaves by the application of distilled water. 



Leaves were i^athered on December I2th, and after two hours placed 

 in distilled water in positions as shown in Fi^. 2. In no case did the 

 cut end of the petiole dip beneath the surface of the water. The leaves 

 had lost almost nothing by transpiration during the time intervening 

 between gathering and placing in the dish of water. 



Leaf. 



Reaction, 24 hours. 



Pelargonium 1 Alkal ...... 



Abutilon ! " 



Rosa " 



Eupatorium " 



Crassula Weakly alk . 



Heliotropium " " . 



Begonia Neutral . . . . 



Panicum Alk 



Impatiens Weakly alk , 



Arabis | " " . 



Primula st Neutral 



Primula ob ! " - . . . 



Tropseolum 1 " . . . . 



Reaction, 144 hours. 



Strongly alkal. 



Alk. 



Strongly alk. 



Acid. 



Alk. 



Strongl}- alk. 



Slightly alk. 



Alk. especially at margin. 



Acid. 



Alk. 



Acid. 



Strongly alkal. 



On leaf, acid, water alk.' 



The water was then allowed to evaporate, which it did in a period of 

 about ten days. The dishes were protected from dust by placing a tray 

 loosely over the top. 



The water had not penetrated into the intercellular spaces of the 

 leaves to any noticeable extent. The amount of substance given off by 

 the leaves was considerable in every case, and in some cases was quite 

 remarkable. When the water had all evaporated from the dishes, and 

 the leaves were removed, a beautiful white "print" of the leaf was left 

 upon the bottom of the glass dish. This " print " was deeper at the 

 margin of the leaf, an^ was composed of feathery white crystals. In 

 the case of three or foi)r of the leaves used, the surface in the neighbour- 

 hood of the vfeins was not in actual contact with the bottom of the dish. 

 Here water lay during the experiment, and in this region there was a 

 prominent accumulation of crystals. Where the leaf surface actually 

 touched the glass there was little or no deposit. This would remove all 

 doubt as to the possibility of dust particles or gases from the air having 

 anything to do with the crystalline deposit. The alkaline or the acid 

 quality of the liquid was peculiar, in that the results in twenty-four 

 hours differ from those in six days, as shown in the table. This is 

 probably due to chemical changes peculiar to the material composing 



