344 



Mr F. Darwin and Mr R, W. Phillips, [Nov. 23, 



Here the first cut diminished the rate by about 30%; the 

 immediate effect of the second cut being a diminution of 77 / o . 

 Partial recovery occurred after the first sawing, but no signs of 

 recovery were seen after the second. 



In a plant such as the Jerusalem Artichoke (Helianthus 

 tuberosus) where the vessels take a larger share in the vascular 

 bundle than they do in woody plants, the effect of the two cuts is 

 greater still, that of the second cut being very strongly marked. 



Exp. 



water). 



13. Aug. 15, 1884. Jerusalem Artichokes (cut under 



p.m. 



5-49 



55 



58 



6-1 



3 



7 



9 



10 

 6-30 



Rate 



143 

 128 



128 



Cut half through 



57 



58 



58 



Cut half through opposite, 2 era. ahove 



2 (about) 



The reading after the second cut was difficult to take, the 

 bubble took about 10 minutes instead of 17"2". But whether 

 or not it is accurately represented in the column of reciprocals 

 by the figure 2, there is no doubt that the effect of the second cut 

 was enormous as compared with the first. 



The same thing is shown in the following experiment : 



Exp. 14. 



water). 



Aug. 15, 1884. Jerusalem Artichoke (cut under 



Rate 



116 



116 



Cut half through 



91 



98 



104 



104 



Cut opposite, 2 cm. above 



2 (about) 



The effect of the first cut is small, and is followed by partial 

 recovery, while the second cut produces a comparatively enormous 

 effect. 



