546 



GENERAL BIOLOGY 



Sympathetic system ... 190, 460 



Synapsis 33 



Synergid nuclei 153 



Synthesis 84 



Synthetic types 248 



Syrphidae 43 2 



System of classification .. 222 



Systems of organs 442 



Tails of sheep 3 J 9 



Tannin 3 8 



Tardigrades 377 



Tarsus 243 



Teeth 127, 183 



Telophase 294 



Telson 231 



Tentacles 157 



Tenthredinidae 44 



Terrestrial life 121 



Testes 188 



Thallophytes 118 



Thallus 119, 129 



Third ventricle 200 



Thoracic duct 213 



Thorax 17, 232 



Thyroid gland 443 



Time adjustments ...... 375 



Tipula - 229 



Tongue 183 



Toolsj 491 



Tool using 487, 490 



Torulae 92 



Toti-potent sperm nucleus 304 



Touch 444. 446 



Tracheae 187, 259, 408 



Tracheal gills 409 



Tracheid 133 



Transformation of insects343,347 



Tree frog 426, 42 7 



Trial and error 481 



Tribal societies 501 



Types of inheritance 308 



Types of nurture . . 214 



Types of symmetry 288 



Upper brain 481 



Ureter 188, 206 



Urinary bladder ...... 186, 198 



Uterus 189, 2 1 5 



Utricularia 252 



Vacuole 58 



Vagus 191,463 



Van Beneden 299 



Variation 267, 268, 289 



Vascular bundles 132, 143 



Vaucheria 65 



Veins 259 



Velvet 365 



Venation of leaf 135 



Venous sinus 187 



Ventricle 187 



Vertebra 180 



Vertebrate characters .... 195 

 Vestigial structures .... 259, 265 



Vesture 21 



Vibrations 446 



Vibratory stimulus 453 



Villi 185, 215 



Viola cucullata 33 



Violet 33, 152 



Vision 445 



Vital relations 7 



Volvox 107, 112 



Von Baer 174 



Vorticella 76, 79 



Vorticellidae 81 



Wars 326 



Warning coloration 449 



Wasp 490 



Water and distribution .. 372 



Water penny 245 



Water vessels 492 



Weaklings 279 



Web 4 



Weevil 5.379 



Whirligig 387 



Willow n, 45, 3 52 



Wind, effects of 401 



Wings 17,225,258 



Wing veins 225, 229, 258 



Winter buds 334 



Witch hazel aphid 341 



Witches' broom 37 



Wood 145, 146 



Woodland plant society .. 373 



Xerophytes 372 



Xylem 145 



Yeast 92 



Yolk plug 194 



Zoaea 343 



Zoochlorellse 394 



Zoospore 333, 340 



Zoothamnium 81 



Zygote 297 



