GENERAL REPOET. 



Plant Evaporation. 



•.. ArTEMI.SIA TridENTATA. y«/j/ 21, 1868. 



* The thermometrical record for this date is given in full in the table on page xxii. 



It must be confessed that these experiments were conducted with too 

 little method and are too incomplete to be fully satisfactory. The amount 

 of loss as here shown is doubtless greater than it would have been from the 

 same leaves and stems when attached to the plant, yet making a probably 

 full allowance for this source of error it appears that the ordinary drain upon 

 the juices of these plants must be large. Comparing the recorded amounts 

 of water evaporated from an open vessel during the same hours with that 



