INI 



505 



Ungulates, development in N. America 

 during Tertiary period, ii. 18 



United States, flora of, i. 432, 433; 

 spread of Darwin's view- in, i. 157, 



159 

 I nity of coloration, Walsh on, 1. 261 

 Uredo, <>n Heematoxylon, ii. 411 

 Ursus arctos, Lamont on, i. 179 ; U. 



maritimus, Lamont on, i. 179 

 Urticacese, i 106 

 Uruguay, i, 1 ; 



.die, on Canary Islands, i. 409 

 Use and disuse, i. 199 ; in plants, i. 389 

 Uses, Natural Selection ami, i. 355. 356 



lallata, i. 20, 22 

 Utilitarianism, Darwin on. i. 328 

 Utility and inheritance, i. 239 



;, Darwin's idea of, ii. 374 

 Utricularia, Darwin's work on. ii. 403, 



404 ; U. stcllaris, Sir E. Tcnnent 



on, ii. 404 



VaGINULUS, Darwin finds new species 

 of, i. 15 



Valeriana^ two forms of. ii. 416 



Valleys, action of ice in formation of, 

 ii. 154. 155 ; Dana on Australian, ii. 

 227 ; Darwin on origin of, ii. 211 



Valparaiso, i. 17 



Van Diemen's Land, i. 41 ; flora of, in 

 relation to New Zealand, i. 405 



Vanda, ii. 306 



Vandeae, structure of ovary, ii. 307 



Vanessa, two sexual forms of, i. 356 ; 

 breeding in confinement, ii. 96; 

 colour of, ii. 67 



Vanilla, ii. 271, 313 



Variability, i. 148, 161 ; backward 

 tendency of, i. 353 : Bentham on, 

 i. 379 ; causes of, i. 155, 19S, . 

 289; De Candolle on, i. 2;;. 23 ; 

 dependent more on nature ol organ- 

 ism than on environment, i 377 : 

 Huxley and Sl.>u on, i. 220; im- 

 iiance of subject of cause of, i. 

 592 : Natural Selection and, i. I 

 in oaks, i. 234 : greater in bisexual 

 than in unisexual plants, ii. 314 ; of 

 ferns "passes all bounds," ii. 3S1 : 

 greater in male than female, ii. 94 ; 

 in ovaries of (lowers, ii. 37S : ten- 

 dency of genera at different periods 

 towards, ii. 231 



Variation, i. 41-6, 96, IOO, 105-7, 

 171, 172, 199, 222 ; an innate prin- 

 ciple, i. 199 ; Hates on, i 181 ; in 

 blackbirds, i. 262 : causes of, i. 155 : 

 centrifugal nature of, i. 199 ; checked 

 by Natural Selection, i. 208 ; climate 

 and, i. 198 ; Darwin attaches import- 



VOL. II. 



ance to useless, i, \iz : I '. : win 



favourable, i. 271 ; 



286 ; and external condit 198, 



354 ; in elephants, i. 207 ; i:. 



i. 102 ; of large genera, i. 98, 107, 



108, 379 ; laws ol, i 13 ; j 



typic and polytypic genera, i. 106; 

 and monsti [47 J5° ; and 



Natural Selection, i. 172, 269-71 ; 

 ordination and, i, 193, 194, 321 ; in 

 peaches, i. 276 ; in plants, i. 41, 102, 

 105-8, 275, 425; ii. 157; produ 

 by crossing, i. 212 ; rate of action 

 i. 314 ; of small genera, i. 107, 108, 

 379 ; sterility advantageous to, i. 290 ; 

 Weismann on, i. 311 ; galls as ^ause 

 of, ii. .125 ; and loss of dimorphism 

 in Primula anil Au 

 Sexual Selection and minute, ii 

 63 ; transmission to sexes, ii. 86 ; 

 Verlot on, ii. 157 ; Wallace on, ii. 



32, 63 



xtion of Animals and Plants n< 



: )l. i. 167, 243. 2S5. 363, 



364: ii. 3S9 ; C'.mpletion of, i. 277, 

 278, 283, 359; delay in publication, 

 i. 286; Lyell on. i. 299, 300; trans- 

 lation of. i. 304 ; Wallace's opinion 

 of, i. 288; Darwin at work on, ii.. 

 150. 192. 327. 404. 405 



Varieties, accumulation of, i. 161, 191, 

 337 ; distinction between species and, 

 i. 177 : fertility of, i. 137 : ii. 309; 

 in insects, i. 5, 94 ; in large genera, 

 i. 402 : of molluscs, i. 94 : production 

 of, i. 47, 212 : species the product of 

 long series of, i. 377 : use of, i. 126, 

 127: Wallace on, i. 118; elimina- 

 tion by crossing, ii. 250 ; z 

 neglect study of, ii. 210 



Vaucher, Plantes 



Masters', i. 148 : 



ii- 335 



itative reproduction, Darwin on, 



i. 221 

 Witch, J., ii. 27. 18 



lisation mechanism of, 

 ii. 2 



og and varieties in, 

 i. 138. 218, 222, - | 231 : ii. s 



309 : Sc itt's work on. 

 ii. 

 oenace.e, i. 107 

 Verlot. on variation in flowers, ii 



u .:. Antacrtic species of, i. 163 

 . as guide to morpho- 

 . .t Sowers, ii. 273-5 : 

 Vestiges of Creation, i. 48. 40. 85 | 

 Huxley's review of. 1. 75 ; the On 

 of S t . 1, i. 136 





