474 



Index 



Sturtevant, 228. 



Sugar beets, variation in amount 



of sugar in, 54. 

 Swede turnip, 248. 

 Swedish Seed Association, 304. 

 Swedish select oats, 313. 

 Swingle, Walter, 312. 

 Systematic improvements of plants, 



295. 



Tangelo, 133, 312. 

 Teas' Weeping mulberry, 233. 

 Teosinte, 137. 

 Thomson, 149. 

 Thymus vulgar is, 80. 

 Timothy, variability of, 3. 

 Toad-flax, 79, 81, 82. 

 Tobacco pollinations, 142. 

 Tomato, 215, 222, 228, 244, 246; 

 ignotum, 246; pollinations, 141. 

 Trihybrid, 177. 

 Tschermak, 155, 188. 

 Tuber-unit, 308. 

 Type, 43. 



Unit-characters, 9, 154. 

 United States Dept. Agri., 310. 

 Uses, breeding for specific, 224. 



Variability, biometrical expression 

 of, 43, 47; coefficient of, 49. 



Variation, action of natural selec- 

 tion upon, 14 ; and adaptation, 7 ; 

 causes of, 13, 30, 94 ; caused by 

 environment ; caused by sex 

 differences, 15 ; in climate, 25 ; 

 choice and fixation of, 34 ; de 

 Vries' classification, 53 ; fluctuat- 

 ing, 54; in food supply, 20; 



measurement of, 41 ; natal and 

 post-natal, 18. 



Varieties, "coming true," 210, 211 ; 

 how they originate, 209 ; inde- 

 terminate, 209 ; non-uniformity 

 of, 19 ; outright production of, 

 by crossing, 118 ; retrograde, 63 ; 

 spontaneous appearance in wild 

 state, 79. 



Variety, what is it ? 35. 



Verlot, 244, 296. 



Vigor as result of crossing, 112, 115. 



Vilmorin, 226, 230, 231, 269. 



Vitis, 122. 



Vries, de, Hugo (see de Vries). 



Walker, Ernest, 243. 

 Wallace, 105, 123. 

 Watermelons, wilt-resistant, 219. 

 Wealthy apple, 233. 

 Webber, 133, 156, 312. 

 Weismann, 16, 17. 

 Wheat, Durum, 313. 

 Wheatland fife wheat, origin of, 91. 

 Wheat-rye hybrid, 136. 

 Wier, D. B., 233. 

 Wild cabbage, 240. 

 Wilks, Rev. W., 76. 

 Willis, 117. 



Wilson, strawberry, 248. 

 Wilt-resistant watermelons, 219. 

 Winkler, Professor, 146, 148. 

 Wisconsin Agricultural Improve- 

 ment Association, 300. 



Xanthein, 187. 

 Xenia, 327. 



Zygote, 327. 



