426 



C. M. CHILL. 



yellowish brown. The color gradients have been determined in 

 KCN m/5O, alcohol 10 per cent., ethyl ether 4 per cent., and 

 HC1 m/ioo, and they are essentially similar in all, though the 

 color changes differ somewhat with different agents. In all 

 these agents during the first 3-4 hours there is a distinct loss of 



FIG. i. 



2 



FIG. 2. 



color beginning in the median apical region and progressing 

 laterally and basipetally. This change involves the apical 5-8 

 mm. of the plant and does not progress further, but shades off 

 basally into a deeper color. After this change the apical region 

 for several millimeters is light grayish green (KCN), yellowish 

 green (alcohol), first deep olive green soon becoming yellowish 

 or whitish green -(ether), or a dirty whitish yellow (HC1). Evi- 

 dently the pigment in this region diffuses out to a considerable 

 extent and the water is often tinged by it. This pigment loss 

 decreases with increasing distance from the apical end, hence 

 the color gradient from light yellowish or whitish apically to 

 deep color approaching normal basally. 



