Index 



881 



Phonoreception, problems of, 473 



transmission in nervous system, 480 

 Phosphagens, muscle, distribution of, 614 

 Phosphoarginine, distribution of, 615 



structural formula, 616 

 Phosphocreatine, distribution of, 615 



structural formula, 616 

 Phosphorolysis, 757 



Photochemical effect, illuminating intensi- 

 ty and, 407 

 Photochemical nature of photoreception, 



405 

 Photochemical reaction, reactions follow 

 ing, 408 

 of photoreception, 440 

 temperature coefficient, 406 

 Photoreception, 381-446. See also Vision. 

 carotenoids in, 408 

 measurement of functions of, 414 

 nonphotochemical theories of, 418 

 photochemical nature of, 405 

 physiology of, 405-440 

 summary of, 439 

 Photoreceptors, electrical activity of, 420 

 localized, 383 



function in orientation, 385 

 morphology, 383 

 pattern vision and, 387 

 See also Eye. 

 Photosensitivity. See Light sensitivity. 

 Phototrophic organisms, 1 1 3 

 Phototropism, 381 

 Phrixothrix, luminescence in, 664 

 Phrynosoma, color changes in, 713 

 Phylogeny, comparative physiology and, 3 

 Physiology, fields of, 1 

 Physostigmine. See Eserine. 

 Phytomonadida, photoreceptors in, 383 

 Piercing and sucking mechanisms, 147 

 Pieris hrassicae, chromatophores in, 691 

 Pigeon, lungs and air sacs of, 221 

 Pigments, absorption spectra of, 299 

 as blood proteins, 334 

 blood, oxygen tension and, 247 

 carotenoid, in vision, 408 

 chemistry of, 294-306 

 dissociation rates of, 297, 298 

 distribution of, 290, 293 



in worms, 294 

 eye, in compound eye, diurnal move- 

 ments of, 388 

 in Drosophila, 730 

 in chromatophores, 678, 680 

 in annelids, 688 

 in Dixippus, 692 

 light sensitivity and, 382 

 molecular weights of, 301 

 nitrogenous, excretion of, 190 

 oxygen transport by, 306-329 

 photosensitive, chemical evolution of, 412 



Pigments, retinal, hormonal control of, 763 



sedimentation rates of, 301 

 Pilocarpine, action of, 561 

 Pinna, 473 



Pinnaglobin, 292, 293 

 Pituitary gland, active principle of, effect 

 on amphibia, 53 

 anterior, adrenotropic principle, 758 

 bird migration and, 767 

 diabetogenic principle, 758 

 effect on carbohydrate metabolism, 



758 

 gonadotropins in, 741 

 growth and, 726 

 thyrotropic principle, 758 

 control of color changes in reptiles, 



712 

 control of reproductive cycles by, 



748 

 effect on color changes in amphibians, 

 704 

 in fish, 709 

 posterior, effect on water balance, 761 

 Placenta, estrogen in, 745 



progestin production by, 746 

 Placohdella parasitica, chromatophores in, 



688 

 Planaria, dietary factors of, 135 

 osmoregulation in, 35 

 photoreception in, 386, 387 

 Planorbis, hemoglobin function in, 324 

 Plasma, concentration of ions in, 93 

 Plasmagel in amoeba, 632 

 Plasmalemma in amoeba, 632 

 Plasmalemma in amoeba, 632 

 Plastron, 223 



Platyhelminths, oxj'gen supply of, 211 

 Platysamia, metamorphosis in, 735 

 PLH, 698 



Plumage, hormonal control of, 765 

 Poikilosmotic animals, 10-14 



definition, 8 

 Poikilothermism, 240-244 

 Poikilotherms, acclimatization in, 348 

 aquatic, body temperature of, 349 

 thermal reception and orientation in, 

 350 

 inhabiting dry air, 353 

 inhabiting moist air, body temperature 



of, 351 

 lethal temperatures of, 344 

 temperature relations in, 349-361 

 Polarity in synaptic transmission, 790 

 Polychaetes, gills in, 213 

 respiratory pigments in, 294 

 ventilation in, 262 

 Polypus, digestion of gelatin by, 164 

 Polysaccharides, 169 

 digestion of, 173 

 distribution of, 170 



