244 



Scientific Proceedings^ Royal Dublin Society. 



aspect leaves, which could receive no direct sunshine, is greater than that for 

 the leaves from the south aspect. Again, the fact that the maximum for tlie 



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shaded leaves of the north aspect is not nearer the midsummer maximum of 

 illumination than the maximum of the south-aspect leaves, indicates that the 

 excessive sunlight of summer cannot be held responsible for the depression. 



