332 APPLICATION OF PRINCIPLES. 



tricts where the Apple and Pear are cultivated for 

 cider and perry, much of the success of the planter 

 is found to depend on his skill or good fortune in 

 adapting his fruits to the soil. (Hort. Trans., i. 6.) 

 Rhododendrons and Kalmias are usually cultivated 

 in peat earth mixed with sand, and yet they grow as 

 well in fresh hazelly loam, without any mixture 

 whatever; and, than these two kinds of soil, none 

 can be apparently more dissimilar. The fine Ame- 

 rican cottons are grown in a calcareous sand, those 

 of India in deep black saponaceous earth : the Ame- 

 rican cotton will not thrive in the latter, nor that of 

 India in the former, as has now been ascertained; 

 and yet the species of Gossypium producing the two 

 qualities have no organic differences which can, so 

 far as has yet been ascertained, explain in the smallest 

 degree the necessity, under which it is evident that 

 they labour, of being provided with different kinds 

 of food. The Alnus glutinosa, or Common Alder, 

 flourishes in wet clayey meadows ; while Alnus 

 incana, or Upland Alder, is equally suited to a dry 

 and high land : we are totally ignorant of the reason 

 of such a case as this. Rhododendron hirsutum and 

 Erica carnea are, in their wild state, confined to cal- 

 careous soil ; while Rhododendron ferrugineum grows 

 exclusively on granite, and Erica vagans on serpen- 

 tine. We are informed by Beyrich {Gardener's 

 Magazine, iii. 442) that " the Pine-apple, in its wild 

 state, is found near the sea-shore ; the sand accumu- 

 lated there in downs serving for its growth, as well 

 as for that of most of the species of the same family. 



