428 



INDEX. 



Weight, loss of 173 

 Welwitschia 140 

 Willow, fruit 3Uu; leaf 1'21 

 Wind, distributing seeds 363: 



distributing spores 356; effect 



on form 313 

 Wings to fruits 364 

 Wintergreen, fruit 302, 30^ 

 Wheat, flower 2,5S ; geotropic 



stem SOO; seedling iiS 

 Wood, in root 71; secondary 113 



Xanthium, fruit 307 



Xerophytes 311, 318 

 Xyleni bundles, of root 72; sec- 

 ondary 109 



Yarrow, inflorescence 257 



Yeast, beer 4'J 



Yew ovule and fruit 239 



Zamia, flower 233 

 Zea, stem bundles 107 

 Zoospores lJi7, 212 

 Zygnema 2o, 401 



