336 



INDEX 



Symmetry, 129 

 Syrphidce, 58 



Tactual discrimination, 66 et 



seq. 



Tetrads, 259 



Thomson, Sir J. J., 24, 127 

 Throw-back, 154 

 Tinged-white sweet pea, 211 

 Tower, W. L., 155 

 Treviranus, 30 

 Trifolium firatense, 150 

 Tschermak, 19, 190, 203 

 Types, primary and subordinate, 



125 

 Twins, 287 et seq. 



Unicellular animals, 240, 330 

 Unit characters, 176, 220, 315 

 Uranium, 23 

 Usher, Bishop, 27 



Variability, acquired, 319 



correlated, 106 



genetic, 319 



coefficient, 99 

 Variate, 97 

 Variation, 14 



continuous, 14, 43, 76 et 

 seq,, 82, 155, 316 et seq. 



Variation continued : 



discontinuous, 14, 43, 66, 



i*5 3 l6 ei se 1- 

 meristic, 130 

 negative, 141 

 similar and simultaneous, 



132 

 substantive, 130, 131 



Wading birds, 38 



Wallace, A. R., 16, 35, 43, 65, 



88, 157 



Webb, Sidney, 295 

 Weismann, 16, 51, 52, 65, 72 tt 



seq., 157, 279 et seq. 

 Wells, Dr. W. C., 42 

 Werner, 25 

 Whale, 52 



Wheat, 136, 233 et seq. 

 Whetham, W. C. D., 23, 41 

 Wilks, Rev. W 7 ., 140 

 Willey, A., 79 

 Wilson, Prof. E. B., 74, 272 et 



seq. 

 Winkler, 321 



X-generation, 306 



Yucca plant, 54 



Yule, G. U., 227 et seq. 



Zygote, 185, 245 



BILLING AND SONS, LTD.. PRINTERS, GUILDFOF.D ENGLAND 



