212 



Plant Genetics 



Darling, C. A., 184 



Darwin, Charles, i, 4, 14, 68, 84, 



136, 158 



Determinants, 13 

 Determiner, 32, 52 

 De Vries, Hugo, 2, 14, 80, 84, 



207 



Dihybrid ratio, 37 

 Disease transmission, 26 

 Dominance, 30, 156; failure of, 45; 



and hybrid vigor, 170 

 Doncaster, L., 204 

 Dose, double and single, 34 

 Double fertilization, 144 

 Drosophila, work on, 93 

 Duplex, 42 



East, E. M., 27, 40, 46, 48, 50, 52, 

 69, 80, 112, 131, 142, 151, iS3, 

 154, 162, 173 

 Elimination factor, 24 

 Embryo, sources of, 117 

 Emerson, R. A., 50, 86, 173 

 Endosperm, inheritance in, 144 

 Engler, Arnold, 22 

 Environment, effects of, 20 

 Enzymes in inheritance, 55, 205 

 Equisetum, sex in, 190 



Eactor hypothesis, 52 

 Fagopyrum, heterochromosomes 



in, 184 



Failure of dominance, 45 

 Ferns: apogamy in, 116; sex 



determination in, 191 

 Fixation of hybrids, 83 

 Floury endosperm, inheritance of, 



iS4 



Fluctuating variations, 70 

 Four-o'clock, inheritance in, 44 

 Fruit fly, inheritance in, 93 

 Funaria, sex determination in, 189 

 Functionless organs and inherit- 

 ance, 25 



Fungi, sex determination in, 185 

 Fusion nucleus, 146 



Gartner, J., 158 



Galton, Francis, 16, 51 



Galtonia, heterochromosomes in, 

 184 



Gametes, purity of, 31 



Gametic correlation, 73 



Gametophytes, inheritance in, 123, 

 138 



Gemmules, 6. 



Genotype, 36 



Geranium, work on, 100 



Germ cells, origin of, 18 



Germinal continuity, 6, 8; selec- 

 tion, 6, 9, 68 



Ginkgo, heterochromosomes in, 

 184 



Hemp, sex in, 195 



Hertweg, Richard, 180 



Heterochromosomes, 178 



Heterosis, 164 



Heterozygosis and hybrid vigor, 



164, 169 



Heterozygote, 35 

 Hieracium, parthenogenesis in, 



116 



Higgins, J. E., 195 

 Homozygote, 35 

 Houstonia, heterochromosomes in, 



184 



Hurst, C. C., 40 

 Hybrid vigor, 158 



Idants, 12 



Ids,- 1 2 



Indian hemp, sex in, 195 



Inheritance: of acquired char- 

 acters, 6, 16; in endosperm, 144; 

 in gametophytes, 138 



Inhibitory factors, 57, 58, no, 128 



Intermediate hybrids, 43 



