I \ hi \ 



i.; 



Walnut, continut d 



plant protein in English • . . IT" 



tree (fig.) 



twig (fig.) 



Warbler, yellow, nest <»f (fig.). 142 



Warm-blooded animals . . IfiO 



Warm milk, moltiplicatioo <»f 



bacteria in 360 



Warmth. ;i condition of the 



growth of bacteria 34 1 



Washing away of soil by 



floods 386 



Wasp fly, beneficial insert . . n 



Wasps, members of Bymenop- 



tera 20 



Waste land, after a fire I figs. I . 381 



Waste materials of photosyn- 

 thesis; 276 



Waste products of IkmIv . . 206 



removed by excretion . . . 2<n; 



Water, a necessary condition for 



growth of bacteria .... 347 

 basis of classifying plants in 



societies 393 



contains bacteria •"•h 



composition of 9 



habitat of plants 323 



sanitary measures forprotecting 242 



supply, stti'lent report on . . 242 



Water beetles, destroyers of 



mosquitoes 42 



Water horehound (fig.) . . 331 



Waterlilies, air supply of . . •".'.»» 



hydrophytes (fig.) 



structure of stem of . . . . 286 



white (fig.) 392 



Water snail, host of liver fluke 77 



Wax, in ear 218 



produced in U. 8., value of . 39 



Waxed paper, in transpira- 

 tion experiment 296 



Weasels, destroyed by hawks . i \'< 



harmful animals 1 56 



Webbed toes, of Bwimming 

 birds i '~ 



Weeds, common, lisi of . . . 



definition of 



in plant succession 400 



reasons for success of . 



seeds destroyed by birds . . . M7 



at 





140 

 148 

 108 



216 



'//•■ to i ■ 



Weevils, damage to beam 

 (fig.) • ■ 

 harmful beetles 



Wheat, ■ monocotyledoi 

 amount produced i>\ i S. . . 

 bread, \ aloe of ai foiMi . . . ] 7 ^ 

 breakfasl food, value i 178 

 cereal (fig.) 



flour, value of as fo< ■•! ... 



Indehiscenl fruit 



map «>f production >>t < I 

 member of grass family . 

 one of first cultivated plant s 



• dlings 1 iiu ) 



Whip grafting- Mi _- 1 . . 

 White blood corpu.-rles 

 White-breasted nuth. 



u hole -rain stat iou , 

 White-crowned sparrow 



bemp ami millet stat ion 

 Whiteflsh, example of a bony 



fish 



White grubs eaten by birds 



White of the eye 



White pine, value of ... . 

 White-throated sparrow 



hemp and millet station . . n> 

 Whole grain station, bir.ls 



frequent ing 149 



Whooping cough, a bacterial 

 rtifleanfi 



e\posUle t0 



Wigglers. larva- of mosquito*-* 19 

 Wild plants, Improvement of by 



man 



Willow, flow . -"l 



Wind-distributed frn." 

 Window-growing plant 



sponse to light in ... 

 Windpipe .... 



Wind-pollinated I rfl of 



grass Family . . 

 characterist ica of 



id pollination 

 Wine, use of yeast in making 

 Wing-Wee air sues of pine 



pollen 



Wing of pine seed 

 Wings, ol birds .... 



Is ^'' 



