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Nevertheles s, fcr the sake of subsequent comparisons, it 

 is surely desirable that all the seedlings used in any 

 comparative study should have been subjected to the same 

 germination conditions, v/hether these be optimal or sub- 

 optimal. It may often be most satisfactory to employ for 

 germination the same temperature conditions as are to be 

 used for later phases of grov/th. It is not, however, the 

 purpose of the present paper to enter into any discussion 

 of this fundar.iental question; such a discussion would 

 require experimental evidence that iias not yet been 

 secured. 



