[Vol. 2, 1915] 



666 ANNALS OF THE MISSOURI BOTANICAL GARDEN 



Explanation of Plate 



PLATE 22 



Fig. 1. a, galactose 2 per cent; 6, lactose 2 per cent; c, check — no 

 sugar; d, raffinose 2 per cent; e, saccharose 2 per cent; f, glucose 

 2 per cent. (Cotton plugs were removed at the time of photo- 

 graphing. ) 



Fig. 2. The two outside tubes contain 1 per cent galactose while 

 the two middle ones contain 1 per cent galactose plus 1 per cent 

 glucose. 



Fig. 3. The small plant was grown on 1 per cent galactose; the 

 larger one on 1 per cent galactose plus 1 per cent glucose. 



Fig. 4. a and b, 2 per cent galactose; c, 1 per cent galactose; 

 d, 0.500 per cent galactose; e, 0.250 per cent galactose; f, 0.125 per 

 cent galactose; g, check — no galactose. 



Fig. 5. Peas (shown in fig. la), showing character of root growth 



when tips alone come in contact with 2 per cent galactose-containing 

 medium. 



