some other similar object. In carrying out this 

 experiment the flowers which were tripped artificially 

 were not cross-pollinated. As a single toothpick or 

 grass stem was ordinarily used to trip a number of 

 flowers on one plant, many of the flowers might have 

 been fertilized with pollen carried on the toothpick 

 from one flower to another on the same plant. 



In carrying out the experiments in 1907 the 

 raceme was taken as a unit and no count was made of 

 the actual number of flowers that were on each raceme. 

 From 11 racemes which developed under natural condi- 

 tions. 49 pods developed; from 36 racemes of flowers 

 from which insects were excluded, 28 pods developed; 

 and from 12 racemes on which the flowers v;ere artifi- 

 cially tripped, 25 pods developed. These results 

 obtained in 1907 substantially agree with those ob- 

 tained in the three succeeding years. 



- 8 - 



