270 



Index 



Species-hybrids, 249. 



Specific characters, composition 

 of, 34. 



Spencer, 50, 51, et seq., 58, 59, 60. 



Spermatozoids, origin of, 174. 



Spirogyra, 132, 139, 149, 169, 171, 

 ^73, 187, 226, 227; Weheri, 171, 

 172: Zygospore of, 171. 



Stahl, 147. 



Star-fish, 235. 



Strasburger, viii, 99, 115, 125, 

 129, 131, 135, 137, 150, 159, 160, 

 161, 162, 170, 174, 177, 178, 183, 

 186, 187, 202, 223, 225, 230, 236, 

 238, 242, 258. 



Sutton, 218, 230. 



Swarm-spores, 149, 164. 



Sword-lilies, 222. 



Symplasts, 209. 



Synapsis, 240, 253. 



Tangl, 185, 209. 



Tape-worm, 213. 



Taxodium, 100. 



Thallophyta, 95, 104, 183. 



Thistles, 98. 



Tonoplast, 152. 



Toxopneustes, 229. 



Transportation-hypothesis, 207. 



Trifolium hybbridum L., 28. 



Trimorphism, 27. 



Trophoplast, 42, 130, 144. 



Turgidity, cause of, 150. 



TURPIN, 114. 



Ulothrix, 164. 



Uridineae, 19. 



Urtica, 106. 



Vacuoles, 150; contractile, 156; 



pulsating, 156; wall of, 152. 

 Valonia, 145. 



Van Beneden, 145, 177, 218, 227, 



228, 229. 



Vaucheria, 140, 141, 142, 160, 187. 



Vanilla planifolia, 149. 



Variability, correlative, 73; fac- 

 tors of, 74; fluctuating, 214; 

 phylogenetic, 74; species-form- 

 ing, 214 ; two kinds of, 214. 



Variations, sudden origin of, 22. 



Variety-hybrids, 249, 254. 



Varieties, how fixed, 31, 32; in- 

 constant, 251 ; result of cross- 

 ing, 249. 



Velten, 205, 206. 



Verbascum blattaria, 182; phoe- 

 niceum, 182. 



Verlot, 29. 



Veronica longifolia, 224. 



Vertebrates, 93. 



ViLMORIN, 25, 91. 



Vines, 14. 



VocHTiNG, 96, 104, 114, 116. 



volkens, g., 14. 



Wakker, 98, 99, 131, 149, 155. 



Webber, 211, 227. 



Weigelias, 26. 



Weismann, 50, 53, et seq., 58, 59, 

 60, 65, 68, 79, 80, 90, 91, 103, 

 110, 202, 210. 



Weiss, 147. 



Went, 131, 137, 140, 154, 155, 156, 

 161, 206. 



Wheat, 222. 



Wheat-hybrid, 222. 



Wheeler, 229. 



Whorls, 25. 



Wichura, 32, 259. 



Willows, 33, 259. 



Wilson, 218. 



Worms, 238. 



Xenia, 210, 211. 



Yucca, 16. 



Zacharias, 42, 137, 163, 175. 



Zea Mays, 211. 



Zimmermann, 144. 



Zygnema, 173, 188. 



Zygosporese, 173. 



