686 



INDEX 



Populations, Mendelian (isolates), 510 



size of, factors determining, 563 

 fluctuations in, 352, 564, 567 

 restraints on, 567-568 



small, drift in, 351-352 



sources and sinks of, 352 



species as, 344, 349-353, 372, 381 

 Porifera {see Sponges) 

 Portal system and portal vein, 88; 89 

 Postglacial time, 488, 493; 502 

 Precipitins and precipitin tests, 101, 369- 



371 

 Precursor substances, 58, 59, 68, 69/i., 70 

 Predators, 463, 565 

 Pregnancy cycle, 247 

 Primates, 470-487, 666 

 Principle (law, doctrine), 5 



of recapitulation, 365 



of uniformitarianism, 334-337, 387 

 Proconsul ape, 484; J+85 

 Progesterone, 248 

 Prolactin, 129, 253 

 Prometheus man-ape, 486; 1+85 

 Prophase, 18-19, 216-219 

 Prosecretin, 69n. 

 Proteinases, 175 

 Proteins, 57, 169, 400, 544 



synthesis of, by plants, 174, 542 

 Proterozoic era, 395, 402-403, 405 

 Prothallus (prothallium), 261; 259 

 Prothrombin, prothrombokinase, 59, 



97-98 

 Protista, 194-195, 632n. 

 Protochordates, 551, 630, 656; 424 

 Protogenes, 400-401 

 Protophyta, 193-195, 598 

 Protoplasm, 1, 8, 12-15 

 Protozoa, 178, 194, 629, 632-633; 552,594 



colonial, 179; 1 80 



metabolism of, 186 



reproduction of, 211-213 



responsiveness in, 190 



succession of, 584 

 Proximal direction, 144n. 

 Psilophytes, 409-410, 597, 611; 594 

 Pteridophytes, 197-199, 597, 611, 615 



life history of, 259-261; 262 

 Pterosaurs, 358-359, 447, 631; 448 

 Ptyalin, 65, 68 

 Pulse, 93, 95 

 Pupa, 368, 435 



Pygmies, Negritos, 524; 512, 526 

 Pylorus and pyloric valve, 66, 68; 69 

 Pyramid of numbers, 572 



R 



Races, chromosome, 348 



concept of, 349-351, 508-513, 528 



Races, as isolates, 510, 512 

 of man, 508-528; 412 

 biological, 508-509 

 sociological, 509 

 Racial traits, 511-513 

 Radiation, adaptive, 378, 432, 439, 461 

 Radiation curve, 492; 502 

 Radicle, 140 



Radio-carbon dating, 492-493, 521-522 

 Rami of spinal nerve, 106, 118; 119 

 Ranges, factors determining, 380-381 



and Jordan's rule, 384-386 

 Ray cambium, 156 

 Ray-finned fishes, 428, 630, 659; 660 

 Recapitulation, 365-368; 864 

 Recent epoch, 394, 488 

 Receptacle, 265; 263 

 Receptors, sensory, 50, 109-115; 117 

 Recessive characters, 281, 347, 352; 285 

 Recombination of genes, 282 

 Red corpuscles, 82; 20 

 Reduction of diploid to haploid, 216-219 

 Reflex action and reflex arc, 116-118; 121, 



124 

 Regeneration, 215 

 Relationships, ecological, 564-586 

 competitive, 564-568 

 cooperative, 568-571 

 evolutionary, 354-386 



biochemical tests of, 369-371 

 and biogeography, 379-386 

 and homology, 355-368 

 and taxonomy, 371-377 

 Rennin, 66, 68 

 Reproduction, 3, 207-210 

 of animals, 211-240 

 asexual, 211-212, 214-215 



in plants, 254, 258-260, 269-271 

 bisexual, 222, 224-230 



and genetic diversity, 347 

 human, 241-253 

 and medium, 552-553 

 of plants, 254-276 

 sexual, in animals, 212, 215-224 



in plants, 212, 255-275 

 unisexual, 224 

 vegetative, 254-255 

 Reproductive cycles, 246-249 

 Reproductive system, human, 26, 241- 



245 

 Reptiles, 631, 661; 594, 662 



origin and history of, 437-453 

 Respiration, 73-77, 186-189; 25 

 and medium, 548-550 

 in plants, 171-172 

 Respiratory system, 25, 73-77 

 Response, 116-124, 190-191, 554 

 Reticulocytes, 83 



