April, 1910.] 



The Bacterial Flora. 



141 



TABLE II. 



Transpiration Data for Solutions Inoculated Jan. 15, 1910, With 

 Pure Cultures of Bog Bacteria. 



in that solution disclose a gradually intensified power of resist- 

 ance and a physiological phase marked by a greater functional 

 activity. The maximum rate of transpiration occurred on the 

 fifteenth day as in the control, while that of all remaining cul- 

 tures appeared on the tenth day. As compared with the control 

 the inoculated cultures, it will be observed, have reduced the 

 transpiration quantity of wheat plants from 20% to 52%. 

 Another matter is the degree in which individual plants vary in 

 tolerance and resistance. When the bacteria are omitted from 

 the sterilized solution no evidence of toxicity is noticeable for the 

 wheat plants growing in the solution, and their variability in 

 growth, and green and dry weight deviates but little from the 

 common norm. But when inoculated the culture medium 

 becomes a condition always active in stimulating or depressing 

 normal functions. The task of securing a co-ordination between 

 functions of absorption, transpiration, and transport becomes, 

 indeed, a complicated one for the plants, varying greatlv within 

 the same species and with diflierent species. The analysis of 

 these experiments has strengthened the conviction that the best 

 functioning plants rather than the general average represent the 

 proper test of the possibilities of agricultural plants under the 

 given conditions, and that adjustment to conditions is a more 



