Index 



533 



Swamps, 99-100, 433-434 

 Swim bladder of fish, 31 

 Symbiosis, 363-381 

 Synecology, 15 



Taiga, 183, 450-451 

 Tarantula, 389 

 Taxis, 207 



Teleosts, osmotic pressure of, 95 

 Temperature, biological action of, 141- 

 159 

 changes, horizontal, 134 

 in time, 131-134 

 vertical, 134-141 

 control of distribution by 150-175 

 control of egg type and sex ratio, 



158-159 

 distribution of, 129-141 

 effect on activity, 156 

 effect on biological rates, 152-155 

 effect on calcium carbonate deposi- 

 tion, 272-274 

 effect on evaporation, 116 

 extremes, adaptations for meeting, 

 144-152 

 limitation by, 160-164 

 in relation to moisture, 181-184 

 morphological effects of, 157-158 

 need for chilUng, 168-171 

 optimum, 155-156 

 results of limitation by, 172-181 

 resistance at various life stages, 163— 



164 

 seasonal vertical changes in water, 



138-141 

 tolerance of extremes, 129-131, 142- 



143 

 variation with altitude, 134-135 

 variation with depth in water, 136 

 Tent caterpillar, geotaxis in, 211-213 

 Teredo, 64 



Termites, 63, 120, 332 

 Territory, 350-357 

 Thermocline, 136, 138 

 Thermoperiodism, 166 

 Thermotaxis, 156-157 

 Thigmotaxis, 61 

 Tidal zonation, 103-107 

 Tidal zone, 101-107 



succession in, 442-444, 446 

 Tides, 101 



Timothy, 225 

 Tolerant plants, 233-234 

 Torrents, see Streams 

 Trace elements, in animal nutrition, 

 297 



in ocean, 287-288 



in plant nutrition, 280-281 



in soils, 285-286 

 Transformers, 467-468, 481 

 Transparency of natural waters, 195- 



198 

 Transpiration, 114-116 



ratio, 122 

 Transport, by medium, 42-53 



of nutrients, in soil, 82-84 

 in water, 301-303, 305-308 



production of aggregations by, 311 

 Tree Hne, 173-176 

 Tree trunks, 118, 440 

 Trees, competition in, 317-318 



fluctuations in growth, 458 



see also Forests 

 Tribolium, 319, 323 



competition in, 396-397 



humidity and reproductive cycle, 

 126-127 

 Tridacna, 274, 368 

 Trophic level, 469-473 

 Tropisms, 207 

 Trout, relation to /)H, 268 



relation to temperature, 155 

 Tundra, 178, 183, 450-451 

 Turnover, 496-497 

 Turtles, temperature requirements, 168 



Ultraviolet radiation, 189, 230-233 

 Unmodifiable factors, 21 

 Upwelling, 305 

 Utrictthria, 393 



Vegetation of North America, 123-126 

 Vegetation types of life zones, 178-180, 



183 

 Vegetative reproduction, 310 

 Vernalization, 169 

 Vertical migration, of insects, 218-219 



of plankton, 217-218 

 Viscosity of medium, 34-42 

 Vision, 202-204 



maximum depth in water, 203-204 



