19 



Conolusions, 



The results sho-r that In certain of the species of 

 plants -under Investigation raaxinum growth may be carried 

 015 when tfanstiiration ia reduced to a minimum, at least 

 during the early period of vegetative growth. 



Where there is a decrease in growth coincident with 

 a checking of transpiration the decrease appears to be 

 due to the inhibition of the elaboration of organic matter 

 rather than by limiting the quantity of mineral salts 

 absorbed. 



In general the checking of transpiration does not 

 appear to decrease the total amount of mineral salts ab- 

 sorbed by the plant, at least for the period of growth 

 during which the plants were under observation. 



The composition of the plant is materially affected 

 by variations in the rate of transpiration, especially the 

 percentages of moisture in the fresh plant and of ash in 

 the dry matter. 



There appears to be no constant ratio between the 

 quantity of dry matter produced and the amount of '.vater 

 transpired, the relation varying according to the envir- 



