the seedling phase, with solutions renewed twice per week. It 

 may be necessary to furnish the plants with mechanical support. 

 The basis of the support should be a cylindrical wooden stake 

 (1/4 -inch dowel is good) and care should be exercised that the 

 leaves are not seriously crowded. The support described by 

 Hibbard (1917) is one satisfactory form. The stake is set in the 

 center of the cork in which the plants are arranged. This phase 

 ends when flowers appear in the controls, but this statement may 

 require modification as the work progresses. 



Plant Measurements at End of Vegetative Period. These are to., 

 be the same as those made at end of seedling period. Of course 

 visual observations on the plants are to be made from time to 

 time through the vegetative period, just as in the case of the 

 seedling period. Especially should the final records show obser- 

 vations on differences in inflorescence, for those cultures that 

 show flowers. 



4. Reproductive Phase. 



Preparation of the Plants. Germination is to be carried out 

 as for earlier phases and twice as many jars are to be set up for 

 the seedling phase as will be needed for the reproductive phase. 

 These cultures are all to be carried through the seedling phase 

 (with the best solution for that phase) just as in preparation 

 for the vegetative phase. Then a selection of one or two repre- 

 sentative cultures is made, for records of plant measurements 

 of the seedling phase, and the remainder are carried through the 

 ve.getative phase, but all with the ^ame solution, which 

 has been found to be best for that phase. At the end of 

 the vegetative phase one or two cultures are selected to repre- 

 sent the average, records are made of plant measurements from 

 these for the vegetative phase, and the remainder furnish the 

 selection for the reproductive phase. This selection is made just 

 as in the case of the vegetative phase described above. The 

 series may of course be in duplicate, etc. ; and triplicate control 

 is introduced as in earlier phases. 



Treatment During the Reproductive Phase. -All of the solu- 

 tions (see below) are to be tested for the reproductive phase. 

 The procedure is the same as for the two preceding phases, with 

 renewal of solutions twice per week. The plants will probably 

 need mechanical support. This phase continues till maturity is 

 reached by the best plants of the series. The exact criteria to be 

 used may receive more attention as the work proceeds; it is of 

 course aimed to find out what set of salt proportions is best for 



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