SUBJECT-INDEX. 



659 



ferentiation, I, 204; division of 

 labour, I, 207, 363^, 367; func 

 tional interdependence, I, 237-9, 

 240-2; autogenous development of 

 units in colonies, I, 364, 367-8, II, 

 620; belief in social evolution, I, 

 432; natural selection, I, 553, II, 

 532; integration and differentia 

 tion, II, 378-9; effects of popula 

 tion, II, 535-6; equilibration, II, 

 537. 



Soil, dependence of plant evolution 

 on, II, 402. 



Solatium jasminoides, organs of at 

 tachment, II, 276. 



Solar system, autogenous develop 

 ment illustrated by distribution 

 of forces in, I, 366. 



Sole, symmetry and location of 

 eyes, II, 205. 



Souia-plasm, Weismann s theory of 

 differentiation from germ-plasm, 

 I, 357, 622, 628-30, 633^4. 



Somites (see Segmentation). 



Special creation: and evolution, I, 

 412, 415, 431; improbabilities, I, 

 418-9, 430, 439, 554; inconceiva 

 bility, I, 420, 429, 431, 554; of in 

 dividuals and species, I, 421-4; 

 the implication of beneficence, I, 

 425-9; summary, I, 429, 554; Von 

 Baer s formula, I, 451-6; verte 

 brate skeleton, II, 551, 556, 565. 



Species: adaptation and stability, I, 

 242; hereditary transmission, I, 

 301-4; variation in wild and culti 

 vated, I, 323-5, 326, 693; gamo- 

 genesis and life of, I, 347-9; phy 

 siological units, I, 362, 364, 369- 

 71, 458, II, 613; indefiniteness, I, 

 389, 445, 572; special creation, I, 

 422-4; instability of homogeneous, 

 and differentiation of, I, 509-11, 

 515, 517-8, 550, 557; persistence 

 of, I, 516, 518, II, 10-11; natural 

 selection and equilibration, I, 

 543-8, 553, 557; non-adaptive char 

 acters, I, 565; morbid products as 

 marks of, I, 567; migration and 

 isolation as causes of differentia 

 tion, I, 568-9; increasing multi 

 formity of aggregate, II, 396. 



Specific gravity, of organisms and 

 environment, I, 174, 177. 



Spermatozoa ) , 



Sperm-cell [ (see Fertilization). 



Sphere: tendency of units to form, 



I, 15; the embryonic form, I, 177; 

 symmetry, II, 131. 



Spheroid, symmetry, II, 132. 



Spiders (see Arachnida). 



Spine (see Vertebrata). 



Sponge: structure and dynamic ele 

 ment in life, I, 119; multicentral 

 development, I, 164; units and ag 

 gregate, I, 185; reproductive tis 

 sue, I, 283; integration, I, 586; II, 

 90, 383; physiological differentia 

 tion, II, 300, 386; development 

 and genesis, 11,463; analogy from, 



II, 576. 



Spontaneous generation: and hete- 

 rogenesis, I, 270; and evolution, 

 I, 696-701, 703. 



Stag, horns and correlated struc 

 tures, I, 567, 670, 676-7, 092. 



Stamens, and foliar homology, II, 

 44. 



Starches: properties, I, 11; trans 

 formations, I, 66, 68, 69, 70, II, 

 593. 



Star-fishes (see Asteroidca). 



Statoblasts, of Plumatella, I, 277. 



Steenstrup, on &quot; Alternate Genera 

 tion,&quot; I, 592. 



Sterility (see Multiplication). 



Stickleback: ova, II, 454; bothrio- 

 ccphalus in, II, 490. 



Stomach (see Alimentary canal). 



Stomata, distribution, II, 260-1. 



Straight line, and evolution hypoth 

 esis, I, 433. 



Strain: compression and tension of, 



I, 151, II, 209-12; relation to 

 mass, I, 155-7; vegetal structure, 



II, 574-88, 592-6; origin of ver 

 tebrate type, II, 600. 



Strawberry: multiaxial develop 

 ment, I, 166; multiplication, II, 

 441. 



Strength, a vital attribute, I, 578. 



Structure: appliances for generat 

 ing motion, I, 75-7; biological 

 classification, I, 125-7, 129; size 

 and organic, I, 137; growth and 

 complexity, I, 138, 145, 161; rela 

 tion to environment, 1, 172-8, 195-6; 

 of unicellular organisms, I, 181-3; 



