THE VISUAL PIGMENTS 



Indicator yellow {contd.) 



stability of, 53 



thermal production of, from visual 

 purple, 84-85 



transient orange, relation to, 45 



unstable form of, 110 



visual purple, relation to, 109-1 14 

 Iodine, isomerising effect of, 134-136 

 lodopsin, 152, 166, 176, 180 

 a-ionone, 141 

 /9-ionone, 141 



s-cis and s-trans forms of, 142-143 

 Iris, 2-3 



/jo-cyanopsin, 154 

 /5c»-iodopsin, 152-154 

 Isoleucine, reaction with retinene,, 106 

 Isomerism (see cis- trans isomerism) 

 /jo-porphyropsin, 154 

 /yo-retinenci a, 138-142, 144-145 



and iso-iodopsin, 152 

 /so-retinenci b, 138-142, 145 

 /jo-rhodopsin, 154 

 Isosbestic point, 23, 85 



Kalitrichus sabacus (Ape), 28 

 Killifish {Fundulus heteroclitus), 33, 37 

 Kinetics of bleaching, 68-75 



Lamina cribrosa, 2-3 



Lepomis pallidas (Blue gill), 34, 40 



Leucopsin or visual white (see also 



Vitamin A), 26-27 

 Lipid, 11, 13 

 Lophopsetta maculata (Sand flounder), 



36 

 Lota vulgaris (Burbot), 28 

 Lucioperca sandra (Pike-perch), 28 

 Lumi-rhodopsin, 47-50, 54, 82 

 density spectrum in dry state at 



room temperature, 49 

 density spectrum in solution at 



- 40°C, 48 

 Lysine, reaction with retinenci, 106 



Maleic acid, 127 

 Mammals, visual pigments of 

 Ape {Kalitrichus sabacus), 28-30 

 Cat, 28-30, 198, 200 

 Cattle, 48-^9, 53, 84, 89, 97, 117, 

 119-120, 136, 144-148, 151-152, 

 154 

 Dog, 28-30 

 Guinea pig, 200-201 



Man, 6, 22-23, 99, 194, 203 



Ox, 99 



Rabbit, 28-30, 33-34, 82-84 198- 



199, 202 

 Rat, 33, 99, 145 

 Sheep, 99 

 Melanin, 1, 13 

 Melanogrammus aeglifinus (Haddock), 



36 

 Mercaptides, 118 

 Merlucius bilinearis (Whiting), 36 

 Meta-rhodopisn (see also Transient 

 orange), 47-50, 54-55, 124 

 density spectrum of, at — 55°C, 48 

 density spectrum of, at room tem- 

 perature, 49 

 identity with transient orange, 49-50 

 in dry state, 49 

 in solution, 48 

 reaction with water, 49 

 'regeneration* of photopigment 

 from, 48^9 

 Method 

 of Partial Bleaching (Dartnall), 



162-169 

 of Photometric Curves (Dartnall, 



Goodeve and Lythgoe), 65-79 

 of Sugar Flotation (Saito), 12-13 

 Methylamine, reaction with retinenej, 



105-106, 108 

 Monoiodoacetic acid (-SH reagent), 



118 

 Morone americana (White perch), 

 45^7 



A^^o-retinenci a, 138-141, 144-145 

 A^eo-retinenci b, 138-141, 144-147, 

 179-180 



and iodopsin, 152 



reaction kinetics with opsin, 145-146 

 Neo-\\X2imm A^ a, 135, 138, 140 



Oncorhyncus Tschawytscha (Chinook 



Salmon), 35-36 

 Opsin (visual purple protein) 

 all trans retinenej a, no reaction 



with, 144-145 

 and regeneration of rhodopsin, 



115-118 

 and structure of rhodopsin, 120- 



121, 123 

 cattle and fish compared, 151 

 cisi retinencg, reaction with, 151 

 c/jg retinencg, reaction with, 151 



212 



