410 



SUBJECT INDEX. 



Mongrels, reversion of, 143 

 Monsters, artificial production 



of, 173 

 Moths, effect of food plants on, 



289 

 Moulds, adaptation in, 375, 377, 



378 



Mouse, evolution in, 350 

 Mutation, DeVries' theory of, 



59 

 Mutations, produced by keeping 



seed, 114 

 Mutilations, non-inheritance of, 



362 

 Mytilus, effect of light on, 252 



N 



Naquada race, correlation in, 

 83 



Natural Selection, action of on 

 variations, 335; validity of, 

 336; in crab, 337; in sparrow, 

 341; in mollusc, 345; in man, 

 347; in mouse, 350; and so- 

 matic variations, 367; necessary 

 in spite of adaptation, 391; 

 produces spines in plants, 391 



Nature, hybrids occurring in, 

 162, 165 



Negative correlation, 73, 79 



Nereis limbata, variation in, 35 



Nervous system, effect of, on 

 skin colour, 256, 257, 259 



Nigella Hispanica, variation in 

 seed capsules of, 89 



Nitrates, effect of, on larvae, 301 



Nutrition of plants, effect of, on 

 development, 200 



Nutrition, effect of, on germ- 

 plasm, 102, 104, 112; on crops, 

 282; on five-leaved clover, 284; 

 on Crowfoot, 284; on Ficaria, 

 285; on molluscs, 287; on bees, 

 287; on aphides, 288; on Lepi- 

 doptera, 288-290; on larvae, 

 291; on tadpoles, 292; on birds, 

 293, 295; on mammals, 294; 

 on spiderwort, 313; on Satur- 

 nia, 317 



O 



(Enothera Lamarckiana, muta- 

 tions in, 60, 61; effect of nutri- 

 tion on, 200 



Optimum temperature of growth, 

 227, 228, 230 



Orchids, hybrids among, 166 



Organic stability, position of, 170 



Organisms, reaction of growth 

 of, to surroundings, 189; vari- 

 able reaction of, to environ- 

 ment, 197; variability of grow- 

 ing, 204; variability of, in 

 relation to environment, 218; 

 variable reaction of, to temper- 

 ature, 230 



Otter, variability of, 221 



Ova, rabbits', transplantation of, 

 119; reaction of impregnated, 

 to temperature, 191, 194 



Oxalis, variation in, 118 



Palcemonetes, variation in rostral 

 teeth of, 27 



Parallel variation, 96 



Parasites, influence of, on crab 

 and on earwig, 40 



Parents, contribution of, to char- 

 acters of offspring, 122; rela- 

 tion of to offspring, 126 



Parthenogenesis, in an ostracod, 

 177; indaphnia, 178; in aphis, 

 179; variability in, 180; affected 

 by nutrition, 288 



Peacocks, japanned, 172 



Pedigree stock, in relation to 

 Law of Heredity, 134 



Peloric flowers, distribution of, 

 in Linaria spuria, 15 



Peloric race, origin of, in Linaria 

 vulgaris, 62 



Penycuik experiments, 140, 148, 

 168, 176 



Periodic selection in mollusc, 

 345 



Periwinkle, variability of, 206, 

 214 



Phylogenetic forms, produced in 

 Lepidoptera, 237 



