3o6 



Transactions of the Canadian Institute. 



[Vol. VIL 



Where the sokition was not of such a nature as that of strong acids 

 or alkalies, but where it followed the veins, it was found that the distances 

 from the base of the leaf to the extreme point of discolourization along 

 each vein was proportional to the total length of the vein, causing the 

 solution to reach the margin of the leaf at all points about the same 

 time (Photos, i, 2, 3). 



Experiments to test the effects of water upon certain leaves when 

 applied to the cut ends of the petioles. Primula obconica. 



Leaves A, B, C, D, E with petioles in distilled water (Fig. 8). 



Leaves F, G, H, I, J with petioles in tap water. 



Examined on December 15th for starch. 



A. — Plenty of starch all through the blade, especially between veins. 



B. — Starch in veins from base outwards. 



C. — Starch in veins ; none at margin ; leaf commencing to wilt. 



D. — No starch. 



E. — Considerable starch in mid-veins ; some elsewhere. 



F. — Abundant starch. 



G. —No starch ; leaf was yellow and dead. 



H. — Starch abundant in distal part of blade ; lobes of base yellow. 



L — Considerable starch. 



J. — Slightest trace of starch near one part of margin. 



