ten minute points at which it was evident that some sort of injury had been inflicted, 

 the most prominent evidence being a more or less marked discolouration. 



Fig. 64. Apricot leaf 

 at the end of the 

 experiment. Com- 

 pare with Fig. 63. 



Fig. 63. Apricot leaf at the 

 beginning of an experiment. 

 Compare with Fig. 64, which 

 represents the same leaf at a 

 later date. 



No. 3. This leaf measured 27 x 21 millimetres on 24th October, 49 x 50 on 4th of 

 November, and 60 x 60 on the 20th November, thus showing an increase of three to four 

 fold during the experiment. It was a young and rapidly growing leaf. 



Nearly all the later holes of this series, and probably all, were visible at the com- 

 mencement of the experiment in the shape of very small blanched areas. 



