INDEX 



271 



Rotifers, 204. 

 Rumplessness, 129, 181. 

 Rust, 129. 



Sacculina, 212. 

 Sadler, 198. 

 Salamandra, 90. 

 Saunders, 129. 

 Scalp muscles, 149. 

 SCHENK, 198, 199. 

 schleiden, 14. 

 Schwann, 14. 



Sea-urchin, 32, 207, 209, 220. 

 Secondary sexual characters, 210. 

 Sedum, 54. 



Segregation of unit characters, 130, 

 145, 175. 



of defectives, 252. 

 Selective fertilization, 202. 

 Serrated leaves, 129. 

 Sex-limited inheritance, 213. 

 Sexual reproduction, 9, 20. 

 Sheep, 67, 179. 

 Sheep, Ancon, 68. 

 Shirley poppy, 63. 

 Shull, 67, 129, 133, 222, 241. 

 Siamese twins, 69. 

 Silk-worm, 129. 

 Simplex dose, 133. 

 SiTOWSKI, 83. 

 Skew polygons, 50. 

 Skin color in man, 196, 231. 

 Smith, 212. 



Smooth-margined nettle leaves, 129. 

 Smooth peas, 129, 134. 

 Snails, 58, 129,-'178, 180. 

 Snapdragon, 129, 173. 

 Social hindrances, 259. 

 Somatic induction, 83. 

 Somatoplasm, 10, 148. 

 Species, 62. 



cycle, 71. 



elementary, 62, 72. 



Linnaean, 60. 



origin of, 1. 

 Speculations about sex, 197. 

 Spencer, 92, 260. 

 Spermatocyte, 23, 211. 

 Spermatogonia, 23. 

 Spermatid, 23. 



Spermatozoa, 21, 23. 



Spermists, 22. 



Spha;r echinus, 32. 



Spines, dermal, 151. 



Spiny ant-eater, 150. 



Spillman, 129. 



Sponges, 7, 8. 



Spontaneous generation, G. 



Spores, 9. 



Sports, 39, 56. 



Spotting factor, 171. 



Spotted mice, 121, 164. 



Sprengel, 63. 



Spurs, extra in poultry, 69. 



Standard deviation, 46. 



Standfuss, 70. 



Starchy kernel, 129. 



Starfish rays, 44. 



Statoblasts, 8. 



Stentor, 16. 



Sterilization laws, 255. 



Stevens, 207. 



Stevenson, R. L., 260. 



Stockard, 39. 



Stocks, double, 63. 



Straight hair, 138. 



Sub-species, 62. 



Sudan red III, 83. 



Sugar beet, 155. 



Sumner, 89. 



Sunburn, 88. 



Sunflower, 129. 



Supplementary factors, 159, 163. 



Survival of the fittest, 226. 



Susceptibility to disease, 93. 



to rust, 129. 

 Sweet pea, 13, 160. 



Taillessness, 68. 

 Tails, docked, 88. 

 Tatusia, 202. 

 Telophase, 20. 

 Tennent, 31. 

 Theory, cell, 14. 



chromosome, 29. 



enzyme, 33. 



mutation, 56, 72. 



nutrition, 198. 

 Theromorphs, 71. 

 Thigh bones absent, 69. 



