INDEX 



227 



Quercus, 88, 90 

 Quetelet, 28, 31, 70, 115 



R 



Race, adaptation of the, 217 

 Radial system, 77 

 Ramification, 89 

 Eana, 19 



Ranunculus, 10, 21 

 Recessive character, 33 

 Reptiles, scales, 8i 

 Reseda, 89 

 Retina, 114 



Retrogressive mutation, 59 

 Rhododendron, 9, 78 

 Root, primordia, 112 

 Rosa, 13, 216 

 RosaceiB, 191 

 Rubia, 6 

 Rubus, 216 

 Rule, law, 40 

 Rye, 17 



Species, constancy of, 215 ; descrip- 

 tion of, 207, 209, 217 ; independence 

 of, 215 ; Jordanian, 216 ; notion of, 

 I, 214 ; monotypic, 14 ; complex, 

 14 ; horticultural, 16 ; bud-, 16 ; 

 seed-, 16 ; origin of, 141 



Specific, energy, 116, 129, 181, 187 ; 

 constants, 174, 176, 218 



Specimen, 71 



Sphere, equilibrium on a plane, Ii5 



Spirogyra, 70 



Sport, 7, 8 



Sprengel, Chr. K., 35 



Spurs, 92 



Steinbrink, 74 



Stellaria, 18 



Stomates, 102 



Subspecies, 7, 11, 14 



Substantive variation, 69 



Symmetry, relation with variation 

 steps, 180 



Symphoricarpus , 91 



Systematics, importance of, 211 



Saccharomyces, 78 



Salicornia, 21 



Salix, 216 



Saltation. See Mutation 



Scalaria, 178, 183 



Sciurus, 28 



Secale, 17, 175 



Seed rarely produced in many species, 



17 



Seed-fixed properties, 16 



Seed-species, 16 



Segregation, 34, 38 ; in hybrids, 34, 

 35, 40 ; by gradation, 45 ; in the 

 course of individual development, 

 46 ; by plasticity, 43 



Selaginella, 78 



Selection, 7, 81, 215, 217 



Senecio, 12, 179, 181, 182 



Sensations, duration of, 49 



Sensitive period, 56, 75, 82 



Serrure, 80 



Sertularia, 81 



Sexual characters, 205 ; secondary, 60 



Shells, collection of Ph. Dautzenberg, 

 24 ; of moUuscs, 98, 113 



Shrubs, 92 



Simple properties, 40 



Skin, human, 98 



Social : cause, difference, environ- 

 ment, 73 ; equivalence, 91 ; rela- 

 tions, 91 



Solanum, nigrum, 8, n ; potato, 16 



Soldanella, 9 



SoUdago, 92 



Tables, of constants, 218 ; of identi- 

 fication, 218 

 Tail (head or), 116 

 Talpa, 81 



Teleutospores, 77, 103 

 Tellina, 109 

 Tetrahedral system, 78 

 Thistles, 11 



Thorpe, Edward, 2, 3, 4 

 Trees, 88, 92 

 Triaxial system, no 

 Trijolium, 89, 178, 180, 193 

 Triodia, 209 

 Tschermak, 35 

 Tulostoma, 81 

 Turkey, 195 

 Types (specimens), 210 



U 



Ulmus, 204 



Units, biological, 71, 84 ; intermediate, 



96 

 Unwin, G., viii 



Value, maximal, 173 ; m-o-M, 172 ; 



minimal, 175 ; optimal, 168. See 



Mean Value 

 Vanda, 99 



Vandevelde, A. J. J., 107 

 Variants, 10 

 Variation curves, 29, 160, 165 



