JUNE. 125 



inviting field will be opened to horticulturists ! At present all our 

 varieties may be said to be owing to hybridisation alone ; the well- 

 known change of the flower of the Hydrangea hortensis, from pink to 

 blue, being almost the only one effected by any thing like chemical 

 principles. But it is time to return from these speculations as to 

 what may be done in future, to what has already been done, and try 

 to classify the almost endless varieties of the Chinese Azalea. 



I. Whites. 



63. Trotteriana (*). 



-}; 



•1 



