INDEX TO PLANT RELATIONS. 



[The italicized numbers indicate that the subject is illustrated on the page cited. 

 In such case the subject may be referred to only in the illustration, or it may be 

 referred to also in the text.] 



Acacia, 199. 



Achillea, 20Z. 



Adaptation, 147. 



Adiantura, 27. 



Aeration, 92, 93, 95, 183. 



Agave, 45, 47. 



Agrimony, 131. 



Allan thus, 116. 



Air, 95, 98, 114, 123, 138. 



Air cavities, 171, 172, 173, 176. 



Air passages, 93, 93, 94, 95. 



Air plants, 97, 98, 99, 100, 101, 



246. 

 Air roots, 97, 98, 99, 100. 

 Alchemilla, 79. 

 Alga;, 1, 2, 87, 99, 107, 109, 110, 



111, 113, 150, 171, 172, 177. 

 Alkaline deserts, 255. 

 Alpine plants, 148, 231, 232, 233. 

 Amicia, 9. 

 Ampelopsis, 63. 

 Aneinophilous, 122. 

 Animals, 119, 131, 123, 128, 145, 



205. 

 Annual habit, 195. 

 Annual rings, 84. 

 Anthurium, 97. 

 Apple, 79. 

 Arauoaria, 74- 



Arbor vita;, 139. 

 Arctic plants, 148, 232. 

 Arrow-leat, 7.V6. 

 Artillery plant, 130. 

 Ash, 116. 

 Aspidiura, 56. 

 Assimilation, 154, 156. 

 Autumn coloration, 241. 



B 



Bacteria, 189. 

 Banana, 88. 

 Banyan, 105, 106. 

 Barberry, 307. 

 Bark, 84. 



Basswood, lie, 201. 

 Beach, 209, 210. 

 Beach marshes, 353. 

 Beach meadows, 353 

 Beach pea, 118. 

 Bean, I40. 

 Bearberry, 313, 314. 

 Beech drops, 157. 

 Beech forest, 145, 343. 

 Beggar ticks, 119, 131. 

 Begonia, 25, 208. 

 Bellflower, 19, 80. 

 Bidens. 119. 

 Bignonia, 115. 



