238 Relations between Growth and Enviroyiment 



capable of constant renewal is desirable in order that the maximum pro- 

 portion of root hairs, the actual absorbing organs, may be provided and 

 renewed as they die of?. The root, with its multiplicity of long slender 



Oct. 6 Nov. 3 Dec. 1 Jan. 5 Feb. 2 Map. 1 Apr. 5 May 3 June 7 July 5 Aug. 2 



Fig. 12. Shoot/Root Ratios for weekly periods. Oct. 6th, 1915 -Aug. •23rd, 1916. 



Nutrient solutions changed weekly. 



\ 



Oct. 5 



V\m. 13, 



Nov.2 Dec.7 Jan.4 Feb.1 Map.7 App.4 May2 June6 July4 Aug.1 



Shoot/Root Ratios for weekly periods. Sept. 2Hth, 191.5— Aug. 15th. 1916. 

 Nutrient solutions never changed. 



branches continually growing in length, fulfils this condition admirably 

 and each addition of an extra lootlet provides an' additional absorbing 

 surface out of all proportion to the quantity of |)lant material used up in 



