208 COLLEGE BOTANY 



LABOEATORY EXERCISES. 



Exercise 1. Prepare a quantity of Pfeflfer's and Crone's solution and 

 fill several wide-mouthed bottles that have been covered with black paper. 



Prepare PfefFer'a solution, omitting the ferric chloride. Put in bottles 

 as above. 



Prepare Crone's solution, omitting the ferrous phosphate. Put in 

 bottles as above. 



Select seedlings that have been grown in wet sawdust or moss and are 

 uniform in size. Suspend in the glasses by the use of notched corks. Com- 

 pare the growths in the various solutions. 



Exercise 2. Similar experiments may be made by using other modifica- 

 tions of these solutions. 



