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PROl'ECTION OF PLANTS — 1923-24 



The following experiments were conducted with three objects in view : — 



1. To determine the proportions to obtain the best growth. 



2. To study the type and amount of growth. 



3. To ascertain the relationship between growth and H-ion concentration. 

 From the previous culture solutions it will be noted that a number of 



inorganic elements have been used. We have, however, no evidence to the 

 effect that these inorganic elements have been used in the correct proportions. 

 Since the salt requirements for fungi are probably the same as for higher plants, 

 a series of culture solutions was arranged according to the method used by 

 Young and Bennett ('22) in their studies of fungi in culture media. A series of 

 twenty-one cultures, using potassium acid phosphate (monobasic), calcium 

 nitrate, and magnesium sulphate was set up. The salts varied in the different 

 solutions by increments of one-eighth and had an osmotic concentration of 

 three and one-half atmospheres. Sucrose was added in equal amounts of 3.42 

 grams per 100 cc. of the culture, thereby giving the culture solution a total 

 osmotic concentration of four and one-half atmospheres. 



In these triangles the individual cultures are numbered according to the 

 row in which they occur and according to their position in the row. The rows 

 are numbered from the base to the apex of the triangle. The position in the 

 row is from left to right. Thus the culture on the extreme left of the first row 

 is numbered 11, the second from the left in the third row is 32, and in this way 

 every culture flask receives a number. 



The method of arranging the concentrations is given in the following 

 table : — 



Special care was taken in the inoculation of solutions so as to obtain 

 uniform growths at the outset. A modification of Hasselbring's ('06) method of 



