INDEX 



295 



Pattern, radiate: as one of three 

 spatial patterns in organism, 8; 

 surface-interior pattern as, 23; 

 repetition of parts in, 57. See also 

 Pattern, organismic 



Pattern, surface-interior, 23, 61. 

 See also Pattern, organismic. 



Permeability: gradients in, 40; in 

 relation to susceptibility, A}\ 

 in relation to excitation, 72; in 

 relation to origin of neuron 

 pattern, 175 



Planaria: susceptibility relations 

 in, 34; external and internal 

 gradients in, 35, 46; respiration 

 gradients in, 47; biaxial heads 

 in, 5 1 ; physiological dominance 

 in, 100; physiological independ- 

 ence of head region in, 121, 125, 

 126; central nervous system of, 

 i43» !49 



Plants: physiological gradients in, 

 27, 29, 40, 47, 51, 53; determina- 

 tion of polarity by light in,5i, 

 60; dominance and subordina- 

 tion in, 99; physiological isola- 

 tion in, 104; absence of nervous 

 system in, 116; disappearance 

 of physiological gradients in, 

 226 



Polarity, physiological, 24, 50. 

 See also Dominance, physiologi- 

 cal; Gradients, physiological; 

 Pattern, organismic 



Polarization, electric: in relation 

 to excitation, 72, 180; in rela- 

 tion to neuron pattern, chap, xi; 

 in relation to electrotonus, 180 



Polyclads: reversal of suscepti- 

 bility in, 34; limitation of regen- 

 eration in, 134 



Potential, electric: axial gradients 

 in, 44; in relation to excitation, 

 70, 260; in relation to oxidation- 

 reduction, 76, 180; in relation 

 to neuron pattern, 173, 256, 258; 

 in relation to development of 

 cortex, 263. See also Polariza- 

 tion, electric 



Preformistic theory: nature of, 

 6, 8; implications of, 7, 9 



Protoneuron, 156. See also Reti- 

 culum, nervous 



Purkinje cell, 164, 166 



Pyramidal cell, 162, 166, 171 



Receptors, position of, in relation 

 to physiological gradients, no; 

 in anaxiate form, 144; evolu- 

 tionary change in position of 

 peripheral, 151; in reflex arc, 

 233; in primitive gradient, 234; 

 localization of, in relation to 

 axes, 247, 249 



Recovery, differential, 36 



Reduction, of KMn0 4 in relation 

 to physiological gradients, 42 



Respiration: in relation to physi- 

 ological gradients, 46; in Plan- 

 aria dorotocephala, 47; in 

 ground nervous tissue, 48 



Reticulum, nervous: morphologi- 

 cal character of, 156; develop- 

 ment of pattern of, 202 ; func- 

 tional direction in, 245 



Rhythms: in excitation, 208, 213, 

 218; in relation to physiological 

 gradients, 218; in heart, 221 



Segmentation: two conceptions of, 

 130; as a repetitive process, 131; 

 in relation to physiological gra- 

 dients, 132, 254, 260; probable 

 ectodermal origin of , 135, 141, of 

 central nervous system, 138 



Self-differentiation: in embryonic 

 development, 120; of head and 

 apical region, 121; of central 

 nervous system, 127 



Sponges: origin of new polarity in, 

 52; myocytes of, 240, 243 



Stcnostomum, physiological differ- 

 ences in asexual and sexual 

 stages of, 134 



Slernaspis, egg polarity in, 54 



Subordination, physiological, 97. 

 See also Dominance, physiologi- 

 cal. 



