The jar is filled at the start with the solution to be used and 

 two liters of new solution is added once each day, by means of 

 a siphon or funnel, the new solution entering through the glass 

 tube above mentioned. The same kind of solution is to be used 

 throughout the germination period. 



Tests on the relation of the nature of the solution and its tem- 

 perature to rapidity of germination in the wheat to be employed 

 have been carried out at Baltimore, and one of the best tempera- 

 tures and sets of salt proportions for this wheat has proved to be 

 25° C. and Shive's solution R5C2 (0.175 atm.). The germina- 

 tion temperature is to be maintained at from 24° to 26° C, and 

 the solution to be used is Shive's R5C2; in 1/10 "optimal" total 

 concentration (osmotic value about 0.175 atm.). This solution 

 has the following volume-molecular partial concentrations of 

 the three salts; KH^POs 0.0018 mol.; Ca(NOOs 0.00052 mol. ; 

 MgSOs 0.0015 mol. No ferric phosphate is to be used in the solu- 

 tion for the germination phase of growth. This solution may 

 safely be prepared, for stock, thirty times as concentrated as is 

 required, so that 67 cc. of the stock solution plus two liters of 

 water will give a rather close approximation to the needed germi- 

 nation solution. 



This stock solution from which the germination solution is to 

 be prepared by dilution (and from which the control solution 

 for later phases of growth is also to be prepared, with the addi- 

 tion of FePO< in that case) thus has the following volume- 

 molecular partial concentrations of the three salts (these values 

 being thirty times the corresponding values given above) ; — 

 K&POs 0.054 mol.; Ca(NOOs 0.0156 mol.; MgSOs 0.045 mol. 

 To prepare the two liters of germination solution required daily, 

 add 67 cc. of this stock solution to two liters of water. The 

 "error" is negligible and this quick method conserves time. 



The seedlings to be, placed in the culture jars for the seedling 

 phase are to be selected for uniformity as to height (4 cm.) and 

 general appearance. Since ten times as many seeds are to be 

 placed on the net as are to be needed after germination, this 

 selection should be as satisfactory as is possible with present 

 knowledge. 



It is convenient to select at once all the seedlings to be used 

 (and some extra ones), lifting them from the germination net 

 with care not to injure the roots nor to bring them into even 

 momentary contact with the hands, table, etc. The seedlings 

 thus selected are placed in one or more glass pans with germina- 

 tion solution 2 cm. deep, so that the roots are in the solution and 



13 



