INDEX 



Trihybridism, 203 

 Trilobites, 144, 145 

 Trisomies, 287-288 

 Triturus, warning colors of, 244 

 Trochophore larva, 140, 141 



of annelids, 143 

 Trypanosoma, 128, 130 

 Tiypsin, 55 



Tschetverikoff, S^S., 84, 207 

 Tubulidentata, 176 

 Tunicates, 157 

 Tiipaia, 35, 180 

 Turbellaria, 134, 138 

 Turbidity, in immune reaction, 57 

 Turel, 209, 273 

 Turesson, G., 211, 213 



Uca, courtship in, 276 

 Ulna, 39 



Ulva, 107, 108-109 

 nlothrix, 107-108 

 Unguiculata, 175, 176 

 Ungulates, 39 



fibula of, 43 

 Uranium 235, 66 

 Uranium 238, 66 

 Urey, H. C, 110 

 Urochordata, 157, 158 

 Urodela, origin of, 167 



aortic arches of, 48-49 



Vandel, A., 307 

 Variation, 5, 263-264 



continuous, 263 



discontinuous, 263-264 



origin of, 86 

 Varves, 63 



Vascular plants, 113-127 

 Vertebrae, formation of, 31 



of Amphibia, 33, 35 



of Chondrichtliyes, 31-32, 33 



of cyclostomes, 31, 32 



of fish, 31-33 



of lamprey, 31, 32 



of mammals, 35 



of Osteichthyes, 33 



of reptiles, 35 



of Rliipidistia, 33 



of shark, 31-32 



specialization of, 33, 35 



typical, 31 

 Vertebral column, 31-35 

 Vertcbrata, 157, 158 



fossils of, 71 

 Vertebrate embryos, recapitulation in, 



48-50 

 Vertebrate eye, compared to cephalopod 



eye, 40-41 

 Vestigial organs, 42-45, 153, 251 



defined, 42 



new functions of, 44-45 



of man, 42-43, 252 

 Vesuvius, 67 

 Viruses, 89 



and origin of life, 91-92 



chemistiy of, 91 



crystallization of, 91 



free-living, 91, 95 



illustrated, 92 



origin of, 95 



parasitism of, 91 



traits shared with living systems, 91 



traits shared widi nonliving systems, 

 90 

 Vision, of predators, 247 

 Visual pigments, 60 

 Vitamin A, and visual pigments, 60 

 Volcanic ash, burial in, 67 

 Volvox, 106-107, 132 

 Voiiicella, 130, 131 

 Voyage of the Beagle, 7, 14 

 Vulpes, 18 



Wagner, M., 270 



Wald, G., 60, 61 



Wallace, Alfred Russel, 9, 12, 13, 26, 78, 



308, 326 

 Warblers, 30, 31 

 Warning coloration, 243-246 

 Water, as a barrier, 272 

 Water snake, 274 

 Watson-Crick model, 228-229 

 Weasel, cryptic coloration in, 240 

 Wegener, 322 



Weidenreich, F., 187, 189, 194, 196, 198 

 Weiner, A. S., 61 

 Weiner, J. S., 192, 198 

 Weismann, A., 80, 81 

 Weiss, P. A., 53 

 Weldon, W. F. R., 237 

 Whale, ear of, 43 



pelvic girdle of, 43 



teeth, and recapitulation, 50 

 Wheat, genome analysis of, 303-304 

 Wheat rust, 237 

 White, E. I., 75 

 White, M. J. D., 229 

 White Mountains, 16 

 Whittaker, R. H., 110 

 Whooping crane, and genetic drift, 259 

 Wiedersheim, R., 42 

 Wild species, effects of man upon, 332- 



334 

 Williams, R. C, 110 

 Williams, R. J., 61 

 Willier, B. H., 53 

 Willis, J. C., 314, 322, 323, 326 

 Wilson, E. O., 237, 276 

 Winge, O., 293 

 Wings, analogous, 41-42 



of running birds, 44 

 Wolff', K. F., 336 

 Woodpecker, red-headed, 27, 28 

 Wright, Sewall, 85, 212, 253, 255, 258, 

 260, 262, 264, 271 



X chromosome, 204-205 

 Xiphopliorus, hybrids of, 279 

 XipJiosura, systematic i^osition of, 58 



^injanthropus, 188 

 Zuckerman, S., 197 

 Zeleny, C., 219 

 Zoospores, 104-105 



S52 



