368 



INDEX 



parts, 53, 140-151; sex, 54; opera- 

 tion in relation to sex, 55-82; means 

 by which affect sex, 74; in man, 57, 

 81; constitution, 131-163, 165-168; 

 chromomeres, 159; crossing-over, 

 141-143; number of breaks, 162; 

 grouping of genes as to function, 

 174-177; elimination of parts, 189; 

 interaction with cytoplasm, 233- 

 239; in hybrids, 44, 266-276; elim- 

 ination of, 266-276; changes in 

 number and grouping, 317-326; 

 breakage, 155, 326-339; grouping in 

 related species, 317 



Cleland, R. E., 339 



Color, of eyes in Drosophila, 29-31, 

 183-185; body in Drosophila, 138- 

 140; in maize, 245-247, 353; in sal- 

 amander, 249-251; in primrose, 

 304; in Antirrhinum, 304; in rab- 

 bits, 305-307 



Color blindness, 85, 89, 90, 98 



Conjugation, of chromosomes, 48; of 

 Protozoa, 309 



Cotton, mutation in, 360 



Cottus, sex ratio, 76 



Crepidula, 79, 82 



Criminals, 202-204 



Crinoid — sea urchin hybrids, 269 



Criss-cross inheritance, 93, 95-96, 103 



Cross fertilization of diverse organ- 

 isms, 266 



Crossing-over, 141-143; frequency of 

 breaks, 162 



Cross-over ratio, 144; see exchange 

 ratio 



Cytoplasm, interaction with chromo- 

 somes, 67, 68, 233; role in inherit- 

 ance, 164; role in development, 

 190, 233 



Datura, 319-322, 336 



Davenport, C. B., 229, 279, 282 



Death, from defective chromosomes, 

 100 



Defective genes, 290 



Defectiveness, in chromosomes, 28, 

 29, 34; in X-chromosomes, 84-90, 

 101; man, 98; Drosophila, 99; fe- 

 male less defective, 101 ; normals 

 from defectives, 132-134 



Defective parents producing normal 

 offspring, 291 ; defective offspring 

 from normal parents, 293-297, 299 



Deficiency, 194-195, 205, 326 



Degenerate chromosome, 128 



Deletions, 328, 330 



Demerec, M., 205, 351, 365 



Determination of sex, 14-20, 58-82 



Development, 41 ; of sex differences, 

 68-70; action of chromosomes in, 

 42, 67, 177; action of genes in, 187, 

 233-239; role of cytoplasm, 164, 233 



De Vries, H., 322, 324 



Differentiation of bodily parts, 165, 

 233-239 



Digametic, 54 



Dihybrid ratios (dependent on two 

 pairs), 114-118 



Dimensions, 223, 225-229, 278-279, 

 302-304 



Diploid, 39, 53, 63, 323 



Dippel, A., 338 



Disharmony in hybrids, 276-280 



Distribution, of X-chromosomes, 90- 

 93, 22, 83-87; of autosomes, 105; of 

 Y-chromosomes, 123 ; three main 

 methods, 129; of genes, 284-286 



Division of chromosomes, 9 



Dizygotic twins, 199 



Dobzhansky, T., 333, 334, 339, 365 



Dogs, hybrid, 278-279 



Domestication, 310-312 



Dominance, 28 ; in sex-linked charac- 

 ters, 94 



Dominant characters, 28 ; inheritance, 

 23-28; sex-linked, 94; resulting 

 from mating of two recessives, 132; 

 lack of dominance, 224 



Double bar, 247 



Double trisomies, 319, 323 



Drosera, hybrids, 276 



Drosophila melanogaster, figure, 24; 

 chromosomes, 20; publications on, 

 35; eye structure, 23, 99, 247-249; 

 eye color, 29-34, 99, 136, 177, 181- 

 185; sex-determination, 59-67; dip- 

 loid, 63 ; triploid, 63 ; sex-linked 

 characters, 99-102, 175; exchange 

 ratios, 141-145; maps of chromo- 

 somes, 161 ; groups of linked char- 

 acters, 168-177; characters in- 

 fluenced by environment, 242, 247; 

 abnormal abdomen, 242; redupli- 

 cated legs, 244; facets of eye, 247- 

 249; giants, 244; breakage of 

 chromosomes, 326-336; gene mu- 

 tations, 340-362 



Drosophila species, chromosomes 

 groups, 337 



Drosophila virilis, 351-352 



Duplicate factors or genes, 185, 205, 

 222 



