-61- 



although for later growth some of these sets of salt propor- 

 tions are undoubtedly very poor and others are much better. 

 It therefore seems safe to continue using Shive's 

 solution r5c2^ 0.1 atm.) in preparing seedlings for solution 

 cultiires, as recommended in the "Plan", or to use any set of 

 salt proportions lying in the middle portion of the triangular 



diagram. shive's P5C8 is IR?),85l.l on the diagram used in the 



"i 

 present studies; that is, 9.8 eighths of all the salt molecules 



placed in the nutrient solution are VMn^OA 1,1 eighths a^e 

 Caflf03)o, and 3.1 eighths are r,!gS04. Such simple solutions as 

 IR3S2 or IR3S3 (both 0.1 atm. ) may therefore be expected to 

 give results about as good as any other. The salts used for 

 solution type I are relatively satisfactory from both the 

 physical and chemibal points of view, and it may be stated 

 that, so far as this study is concerned, they are just as 

 promising as any of the others. 



It should be kept in mind also, that the solution 

 used for the preliminary preparation of wheat seedlings for 

 solution cultures ought to have a considerable total concen- 

 tration, Distilled water was markedly less efficient than 

 any of the solutions used in these tests, Ij seems safe to 

 recommend a total concentration at least as great as that 

 here used. Perhaps a still higher concentration might 

 give even better growth, but no evidence with regard to this 

 question is available. 



