INDEX 



(References to illustrations are indicated by asterisks accompanying page num- 

 bers. When an asterisk precedes the citation of a group of pages it means that 

 several illustrations are included.) 



Absorption of carbon dioxide, 15, 16 



Absorption of water by roots, 7-9 



Acacia, flower of, 353* 



Acacia, leaf of, 66* 



Accessory buds, 92, 93* 



Acorns, sprouting, 403* 



Actinomorphic, 108, 109* 



Adventitious buds, 92 



Aerial roots, 30, 31*, 32* 



Agaricus, 249 



Agave, 75, 76*, 77* 



Agriculture, 3, 159, 167, 434-459. See 



also under Plant Breeding and 



Weeds 



Ailanthus fruit, 150* 

 Air, relation to germination, 139, 140 

 Air chamber, 14* 

 Air passages, 29, 30 

 Air plants, 31*, 32, 33, 381, 382, 489* 

 Air roots, 30, 31*, 32*, 33 

 Air storage, 76 

 Akene, 328 

 Albugo, 223 



Albuminous substances. See Proteins 

 Alfalfa, nitrogen production by, 37 

 Alga-fungi, *213~225 

 Alga-fungi, summary of, 223, 224 

 Algae, 159, * 180-212 

 Algae, classification of, 212 

 Alsophila, 276 

 Alternate leaves, 55, 56* 

 Alternation of generations, 263-265 

 Ament. See Catkin 

 Angiosperm, life history of, 328, 329 

 Angiosperm flower, 20, 21, 104-114, 



*322-328 



Angiosperms, 158, *32 1-334 

 Angiosperms, summary of life cycle, 



329 



Animal food, plant sources of , 2, 1 7, 82 

 Annual growth, definite, 95, 304 

 Annual growth, indefinite, 95 

 Annual ring, 12, 50*, 51, 304 

 Annuals, 12, 33, 34 



Anther, 20*, 21, 110*, 323 



Anther, modes of opening, 111* 



Antheridium, 201, 261*, 269*, 284* 



Anthoceros, 272*, 273, 285 



Anthrax, 165, 171 



Antipodal cells, 21*, 117*, 325 



Antitoxins, 172, 173 



Apetalous, 106* 



Apple, leaf arrangement of, 56* 



Apples, 454*, 459, 460, 494 



Aquatic plants, *479-481 



Arbor vitae, 310*, 312 



Archegonium, 260*, 270*, 285*, 306* 



Aristolochia stem, cross section of, 



45* 



Arrangement of leaves, *55-60 

 Arrowhead, 478* 

 Ascocarp, 230*, 231 

 Ascomycetes, *226-234 

 Ascophyllum, 207 

 Ascospores, 228 

 Ascus, 228, 230* 

 Asexual generation, 264 

 Asexual reproduction, 194 

 Asparagus flower, 109* 

 Asparagus rust, 245 

 Associations, plant, 455, 495, 496 

 Avens, fruit of, 154* 

 Axil, 92* 

 Axillary bud, 92* 

 Axillary inflorescence, 515* 



Bacteria, 36, 37, 161-179, 162* 



Bacteria, classification of, 179 



Bacteriology, 159 



Bald cypress, distribution map, 504* 



Balsam, wild, flowers of, 130* 



Balsam, wild, fruits of, 153* 



Bamboo, 337 



Banana, 349*, 350 



Barberry, 245 



Bark, 46, 50* 



Barley, 455, 457 



Basidia fungi, 226, 240 



