732 



Index 



Pigment cells, 372 



differential sensitivity to hor- 

 mones, 513, 514, 515 

 genotypic constitution of, 



513, 514 

 "infective" transformation of, 



515 

 invasion into feather germ, 



504 

 migration into skin, 503, 504 

 neural crest origin of, 502, 



503, 513 

 rhythmic pattern formation 



and, 515 

 tissue environment and ex- 

 pression of, 514-515 

 Pigmentation pattern, feather 

 papilla locus and specificity 

 of, 514 

 formation by pigment cells, 



513-514 

 genotype of pigment cells 



and, 513, 514 

 reactions between pigment 



cells in, 515 

 sex-hormone effects on, 514— 



515 

 tissue environment effects on, 

 514-515 

 Pioneering nerve fibers, 359, 362, 



382 

 Pituitary in regeneration, 686 

 in teratogenesis, 710 

 See also Anterior pituitary. 

 Pituitary-adrenal system, adren- 

 aline in, 590-593 

 Placenta, insulin transportation 

 and, 607 

 parathyroid hormone and, 612, 



613 

 transfer of antibodies by, 564 

 transfer of erythrocytes by, 

 566 

 Planaria, head as organizer in re- 

 generation of, 668 

 nervous system as organizer in 



regeneration of, 668 

 regeneration of, 664. 665, 668 

 Plasma, marginal, 230, 233, 234 

 Plexus formation, 346, 359-360, 



384 

 Polarity in annelid regeneration. 

 665 

 in ascidian regeneration, 665 

 in planarian regeneration, 664 

 of sea urchin egg, 665. 666 

 in Tubularia regeneration, 665 

 Polarizing factors, 350 

 Polyploidy and development, 134- 



137 

 Polyspermy, block to, 194-195 

 Preformation, 3, 6, 7 



influence of microscope on, 6, 7 

 Malpighi and, 6, 7, 8 

 Weismann's contribution to, 19 



Preganglionic autonomic cells, 



378 

 Primitive streak, blastopore and, 

 301 

 de-epithelization of, 304 

 Hensen's node and, 302 

 induction capacity and, 306 

 mesoderm formation and, 

 302. 304 

 Primordial germ cells, 175, 176, 

 177, 471-473 

 bipotentiality of, 474 

 crescent of, 471, 472 

 gonad formation and, 473 

 migration of, 472 

 source of, 472 

 See also Germ cells. 

 Progressive differentiation in am- 

 phibians. 230-296 

 in annelids and mollusks, 



318-321 

 in birds and teleosts, 297-314 

 in ctenophores, 321 

 in echinoderms, 327-331 

 in insects. 337-345 

 in selected invertebrates. 315- 



336 

 in teleosts and birds, 297- 



314 

 in tunicates, 321-323 

 Proliferation. 353, 354, 358, 381, 

 383, 389 

 rate of, 378, 381 

 regional patterns of, 374—375 

 Proliferative patterns, 373 

 Pronephric area, position of, 463 

 Pronephric duct. 362 

 Pronephros, differentiation of. 

 465-466 

 dorsoventral axis of, 465 

 Proprioceptive fibers, 385 

 Prospective significance of gas- 

 trula areas, 235 

 of neurula areas, 247 

 of tail area, 249 

 Prostate, castration effects on. 483 



reaction to sex hormones. 481 

 Protein as energy source, 533, 534. 



535. 536. 537 

 Protein fibers, chemical identifi- 

 cation of, 50-51 

 classification of. 47 

 configuration of. 46 

 hierarchy of fiber sizes, 47— 



49 

 repeat period in, 47 

 Prothoracic gland, 638 

 hormone of, 641 



action on tissues, 641 

 Protoplasm, colloidal organiza- 

 tion of, 41 

 paracrystalline state of, 53-54 

 particulate systems of, 42 

 sol-gel transformations of, 54- 

 55 



Protoplasm, tactoids and long 

 range forces in, 53-54 

 water and dissolved substances 

 of, 42 

 Pupation, hormonal control of, 

 639, 640, 642-644 



Rabbit, brachydactyly in, 709 

 Rat, chemical teratogenesis in, 

 702 



gray-lethal mutant in, 703- 

 704, 708 



vitamin deficiency as terato- 

 genic agent in, 701, 712 



x-rays as teratogenic agent in, 

 701, 715 

 Reaction potency. See Compe- 

 tence. 

 Receptor, 351 

 Regeneration, amino acids in, 672 



in amphibians, 677-686, 690- 

 693 



in Amphioxus, 675 



in annelids, 665, 668 



in ascidians, 664, 665, 666, 667, 

 668. 671, 672 



in birds, 689, 690 



blastema of, 369, 679, 680, 681- 

 683, 692 



of bone, 690 



compensatory, 828. 674-688 



competition hypothesis of, 669- 

 671 



control by inhibition, 670 



of cornea, 512, 689 



in cyclostomes, 675 



dedifferentiation in, 667, 679, 

 680 



definition of, 674 



of ear, 415 



electric potentials in, 668 



endocrines as controlling factor 

 in, 685. 686 



environment as controlling fac- 

 tor in, 671 



of epidermal ridges. 512 



of epidermis, 512. 689 



of eye, 409-412, 690. 693 



of feather, 689 



fields, 677, 678 

 of glands, 690 



growth of organs (or parts) 

 and, 627 



of head structures, 685 



induction in, 667, 668, 678, 693 



inhibition of, 669, 670, 671 



in insects, 341 



of intestine, 690 



in invertebrates, 664-673 



of lens, 410-412, 690-693 



of limb, 677-687 



limits of, 627-629 



of liver, 456 



in mammals, 689-690 



of muscle, 690 



