Subject Index 



591 



Phaseolus vulgaris, 323, 324 



Phenotype, 20 



Phenotypic ratio, 83, 128, 129, 137, 



139, 140, 157 

 Phleum pratense, 435, 466 

 Phoradendron flavescens var. macro- 



phyllum, 505 

 Phoradendron villosum, 505 

 Phrynotettix, 487 

 Pine, hybrid vigor in, 388 

 Pinus Thunhergiana, 440 

 Pistillate flowers, 503 

 Plant breeding, 85, 86, 141, 142, 235, 



367 ff., 437 

 Plasmagene, 306 

 Plasma membrane, 3, 5, 12 

 Plastids, 3, 540, 541, 542 

 Platypoecilus xiphidium, 483 

 Pleitropy, 21-23 



Plural determiners, 354, 355, 357 

 Poa pratensis, 435 

 Point mutation, 227 

 Polar body, 49, 149, 424. 425. 426 

 Polar nuclei, 52, 442, 443 

 Polarized chromosomes, 53 

 Pollen grain, 51, 60, 392. 540 

 Pollen tube, 51, 52, 392. 421. 540, 



541 

 differential growth rate of. 272, 



277 

 Polygamous plants. 503 

 Polygenes, 344, 34S, 372 

 Polygenic characters. 357. 358 

 Polyhybrids, 139, 140, 141, 142 

 Polymeric genes. 346, 347, 348, 349, 



351, 353, 354, 357 

 Polymery, 343 ff. 

 Polypeptid fibers. 77 

 Polyploids, 330, 353, 354, 433 ff. 

 evolution and, 453, 531, 533 

 methods of inducing, 471 

 monosomies in, 415 

 origin of, 470 ff. 

 Populations, 264, 351, 359 ff., 386, 



387 

 comparison of by index frequen- 

 cies, 525, 526, 527, 528. 529, 



530, 531 



Populations {continued) 

 gene frequencies in, 537-540 

 heterozygous, 140, 141, 142 

 in equilibrium, 539 



Portulaca grandiflora, 258, 259 



Position effect, 264, 265, 266, 267, 

 395, 401, 518 



Postheterokinesis, 72 



Poultry, see Fowl 



Presence and absence hypothesis, 

 105 



Prime types in Datura, 407, 408, 409 



Primula, 332, 333, 334, 335, 458 



Probability, 86, 108 ff ., 179 

 of occurrence, 120, 135 



Probable error, 117, 359, 361, 363. 

 364 



Prochromosomes, 223, 224, 492 



Progeny test, 377, 382 



Prometaphase, 7, 9, 58 



Prophase, 7 ff., 8, 13, 16, 52 ff., 72, 

 75, 221 



Proteins, 6. 305, 306 



Protenor type of sex inheritance, 69 



Protoplasm, 2 



Pure line, 371, 374, 378, 387 



Pycnotic chromosomes, 476 



Quadrivalent configuration, 204, 445. 



446, 447, 448, 449, 453, 459, 462 

 Quadruplex, 448, 462 

 Qualitative characters, 346 

 Quantitative characters, 342 ff . 

 Quantitative effect at hairy wing 



locus, 266, 267 

 Quinquevalent configurations, 453 



Rabbits, blood groups in, 283, 290 



body size in, 355 



coat color of, 278, 313, 355 



effect of colchicine on, 476 

 Radiation, action of on genes, 267 ff . 



deletions and, 194 



gene mutations and, 241, 243, 251, 

 252, 253, 254, 255, 263, 267, 

 268, 269 



translocations and, 191 

 Radish, 459 



