INDEX 



661 



Hybridisation in maize, 295 



in sweet peas, 300 



in the rose, 310 



of alfalfa, 348 



of maize, 344 



of wheat, 345, 347 



pollination, 343 



practised by Thaer, 288 

 in China, 287 

 in Holland, 287 

 in Italy, 287 



protection of flowers, 344 



Bpeoies, 219, 249, 342, 351, 515 



systematic procedure, 343 



variety, 248 

 Hyde, fertility, 553 



Hydrogen ion concentration in plants, 413 

 Hyperchimera, 375 



Hypothesis of factor contamination in heterozy- 

 gotes, 190 



of factor variability, 192, 193 



of reaction systems, 242, 248, 575 



Ideal of breeder, 342 



Ideas, erroneous in breeding, 449 



Illinois corn-breeding experiments, 327 



rdle of selection in, 329, 333 

 Immunity, acquired, 528 



breeding for, 529 



indirect, 528 



to disease, 404, 527 

 Inbreeding, as a system, 581 



coefficient of, 598 



curves of, 600 



Darwin's idea of, 553 



in maize, 325 



not harmful in itself, 553 

 Increased vigor in species hybrids, 230 

 Index numbers, selection, 334, 502 

 Individual plant selection, 340 

 Infection of male, 571 

 Infectious chlorosis, 381 

 Ingersoll, increased yield from hybrids, 354 

 Inheritance, blending, recognized by Castle, 188 



critical problem of, 4 



intensity of, 459 



of acquired characters, 6, 480 



of aleurone color in maize, 83, 105 



of black and curved in Drosophila, 113 



of coat color in horses, 467 

 in mice, 94 



of coat characters in guinea-pigs, 86 



of corolla length in tobacco, 181 



of defects, 524 



of disease, 522 



of effects of use and disuse, 491 



of endosperm texture in maize, 84 



of fecundity in fowls, 560 



of flower characters in snap dragons, 90 



of larval pattern in silk worm, 209 



of pigmentation in hooded rats, 186 



pf predisposition to disease, 523 



Inheritance of sex, 65, 196, 204, 205, 211, 212 



of size differences, 185 



of unusual sex-ratios, 546 



of vestigial wings, 87 



of white-eye color, 74 



quantitative, 174, 185, 194 



three types recognized by Castle, 189 

 Insects, grafted, 382 



injurious, 400 



ex-determination in, 210 

 Interactions, types of factor, 167 

 Interference, 122 

 Intermediate, condition in F\ species hybrids, 227 



expression in the hybrid, 147 

 Internal secretions and dimorphism, 276 

 I nt ergon eric hybrids, 296 

 Intersexes, in gypsy moth, 217 



in Lymantria, 216 

 Interspecific hybrids, 296, 297 

 Introduction, seed and plant, 299 

 Investigation, genetic, 4, 591, 609 



methods of conducting, 591 



need of biochemical, 413, 485 



of a natural chimera, 378 

 Isolation of pure lines from populations, 256 



Janssens, crossing-over mechanism, 115 

 Jeffrey, sterility of hybrids, 234 

 Jennings, development, 10 



regression, 56 



Jesenko, wheat-rye hybrids, 236, 237, 238 

 Johannsen, bean mutations, 367 



gene, 71 



genotype conception, 329 



mathematics in biology, 56 



Princess bean, 250 



pure lines, 7, 252, 253, 254, 255, 256 



regression, 56 



selection, 250, 366 



summary of Mendel's results, 79, 80 



variation, 439 

 Johnson, tobacco, 418 

 Jones, A. N., grains, 296 

 Jones, D. F., heterozygosis, 559 



vigor of hybrids, 231, 326, 364 

 Jones and Hayes, corn, crossing varieties, 360 



tomatoes, 363 

 Journal of Heredity, 300 

 Judging the individual, 591 

 Juglans californica var. quercina, 265 



californica X nigra, 297. 364 



californica X rcgia, 364 



nigra X regia, 364 



Keeble and Pellew, heteroeis, 232 



vigor in F\ hybrids, 326 

 Keeping varieties pure, 341 

 Kellerman, Miss, preserving pollen, 350 

 Kent, correlation in poultry, 507 

 Khang-hi, imperial rice, 287 



