find that the quantity of water transpired by some of our 

 conamon field crops during their period of growth is not a 

 measure of the amount of dry matter formed. That the 

 ratio between these quantities is not constant is shown by 

 the following table which gives the amoxmt of water trans- 

 pired per unit of dry matter, as determined by different 

 Investigators. 



TABLE 1. 

 La^s and 



Gilbert Hellriegel Wollny King 



PS9 



310 



402 



330 



292 



in commenting on these results. Hall (5) says, "The 

 divergencies in these results are intelligible if we con- 

 sider that the transpiration process by which the rmter 

 is lost and the assimilation process by which the plant 

 gets heavier have no necessary connection, tho both become 

 active under the same stimuli of light and r.-armth." 



