SUBJECT INDEX. 



415 



Variations, swamped by inter- 

 crossing, 57, 58; relation of, 

 to variable environment, 197, 

 199; and modifications, 223; 

 adaptive, 371; definite and 

 indefinite, 371 



Varieties, sterility between, 69 

 Variety, replacing type form, 91 

 Ventricosity, variability of, in 



periwinkle, 206, 215 ' 

 Vetch, effect of water on, 265 

 Volume of water, effect of, on 

 growth of snail, 302; of tad- 

 pole, 306; of Daphnia, 308 



W 



Waltzing mice, reversion in, 142 

 Warmth, effect of, on Lepidop- 



tera, 233 

 Weight, human, variability of, 



205 

 Willow, interchange of root and 



stem in, 376 

 Wolf, variation in, 328 

 Woman, variability of, 205 



Zebras, crosses with, 168 



THE END. 



