282 SOME RECENT RESEARCHES IN PLANT PHYSIOLOGY 



blossoms. These look very beautiful against the other- 

 wise black branches. The flowers of this plant are, of 

 course, normally of a red colour. Probably the removal of 

 the branch results in the cutting off of the sugars which 

 ascend in the vessels of the wood, and are derived from the 

 carbohydrate reserves of the root and stem.* 



In Table LXIV. are quoted Combes 's analyses of red and 

 green foliage leaves. Those of Ampelopsis were gathered 

 on August 5. The leaves which were red had matured 

 more rapidly than the others on the plant, owing to the 

 fact that they were in a very well illuminated position. 



In Spiraea the red leaves were borne on branches from 

 which a ring of cortex had been removed, the green on the 

 untreated portions. Both were gathered on the same day. 



TABLE LXIV. 



CARBOHYDRATES OF RED AND GREEN LEAVES: PERCENTAGES or DRY 



WEIGHT. 



