INDEX OF SUBJECTS 



{The numbers in heavy type indicate the principal references to the subjects.) 



Absorption, 6 



by visual purple, 13, 205 

 Achromatic acotopia, 14, 53 

 Achromatopia, 186 

 Action-time, 90 



chromatic, 91, 235 

 Adaptation, 17, 49, 203, 254 



in dichromats, 174 

 Adequate stimuli, 19 

 After-images, 101, 218, 254, 272, 280 



fading of, 110 

 Akyanoblepsia, 180 

 Allonomous equilibrium, 252 

 Amphibia, anatomy, 11, 15 



colour vision of, 142 

 Amphioxus, 145 

 Anatomy, 7 



comparative, 10, 142, 196 



o 



Angstrom unit, 4 



Animals, vision of, 131, 196, 203, 298 



Annulus, 5 



Anomalous trichromatic vision, 159, 182, 



216, 235, 243, 266, 288 

 Apperception, 24 

 Approximate dichromatism, 235 

 Area, light, 119 



rod-free, 10, 203 



sensibility, 119 

 Areal effects, 51, 79, 95, 97, 117, 180, 250 



in anomalous trichromats, 185 



in dichromats, 180, 250 

 Autonomous equilibrium, 252. 



Bidwell's ghost, 86, 88 

 Binocular contrast, 129, 262, 276 

 Binocular struggle, 276 

 Birds, anatomy, 11, 15 



colour vision of, 140 

 Black, 25, 36, 103, 201, 202, 251, 276 

 Bleaching of visual purple 13, 55, 206, 212 

 Blind spot, 8, 129 

 Border contrast, 127 

 Brightness, 28, 42, 96, 100, 223, 236, 294 



specific, 256, 267 

 Brown, 25, 36 



Cerebral centres, 277, 292 

 Charpentier's bands, 87 

 Chemical changes due to light, 12 

 Choroid, 8 

 Chromate test, 242 



Chromatic scotopia, 53 

 Chromatic threshold, 19, 60 

 Coefficients, law of, 107 

 Coefficient of vai'iation, 149 

 Colour blindness, acquired, 160 



facts, 158 



in primitive races, 147, 148, 150 



partial, 158 , 



theories, 193 



total, 159 



unilateral congenital, 180 

 Colour diagram, 37, 213, 216, 229 

 Colour equations, 38, 213, 226 

 Colour, extinction of, 61, 121 

 Colour ignorance, 161 

 Colour mixtures, 33, 162 

 Colour names, 160, 296 

 Colour sensations of dichromats, 161, 180 

 Colour triangle, >7, 213, 216, 229 

 Colour vision, evolution of, 130. 282. 285, 

 294, 298 



of primitive races, 145 

 Colours, fundamental, 214, 220, 230, 258 



invariable, 70 



memory, 22 



pigment, 6, 78 



simple, 25, 27, 104, 220, 224, 251, 276 

 Comparative anatomy, 10, 142, 196 

 Comparative psychology, 131, 211, 298 

 Complementary after-image, 101 

 Complementary colours, 35, 101, 128, 226, 



254 

 Complete fading, 261, 275 

 Conditional reflexes, 134 

 Cones, 9, 196, 203 

 Contrast, binocular, 129, 262 



border, 127 



luminosity, 127 



simultaneous, 17, 125, 219, 255, 264, 

 279. 



successive, 101, 219, 254, 279 



surface, 127 

 Critical frequency method, 96 

 Curve, equal-area, 228 



luminosity, 42, 172, 189, 223, 240 



minimal field, 72 



minimal tinu;, 74 



peripheral luminosity, 71, 173 



persistency, 62 



sensation, 232 



valency, 215 



