354 PRINCIPLES OF BIOLOGICAL MICROTECHNIQUE 



osmium tetroxide, 24, 32, 51, 61, 

 70, 80, 81, 83, 87, 118, 142, 

 203, 205 

 as colouring agent, 306 



osmotic pressure of fixatives, 83 



Othmer, 91 



Overton, 109, 285 



oxalic acid, 239 



oxazine dyes, 171, 180, 216 



oxidation-potential of fixatives, 90, 

 93,97, 100, 105, 112, 119, 127, 



134 

 oxyflavones, 281 



Palade, 75 



palmitic acid, 94, 121 



Panijel, 227 



Pantin, viii, ix 



Pappenheim, 230, 272 



parabenzoquinone, 157 



paraffin embedding, shrinkage by, 



77, 79 

 paraformaldehyde, iii 



Paramecium, 289 



paranuclear bodies, 281 



paraquinonoid ring, 157 



pararosaniline, 158, 170, 225, 251, 



285, 321 



penetration of dyes, 216, 221, 234, 



285 

 of fixatives, 29, 37, 67, 91, 94, 97, 



102, 108, 116, 123, 131, 136, 



150, 318 

 of vital dyes, 285 

 pepsin, 55, 93, 97, Id, 113 

 peptide link, 45, 59 

 Perenyi, 143, 145, 147 

 perfusion, 25 

 period of fixation, 29, 60 

 per-perosmic acid, 119 

 peritrophic membrane, 275 

 Perls, 304 

 permeability of tissue-constituents, 



influence on dyeing, 234 

 Peters, 287, 288 

 Petit, 20 



Pfeffer, 234, 274, 280 

 pH of mordants, 212, 221 

 phagocytic cells, 260, 276, 280, 297 



phase-contrast microscopy, 28, 275 

 phenylalanine, 192 

 phloxine, 171, 179 

 phosphatidic acid, 94 

 phospholipids, 217, 222, 291, 300, 



301, 302 (see also lecithin, etc.) 

 phosphomolybdic acid, 239 

 phosphotungstate, 248 

 photographic reducers, 305 

 ^-hydroxybenzoic acid, 30 

 physical properties of fixed tissues, 



86 

 picric acid, as differentiator of 



mordant dyes, 222 

 as dye, 174, i85> iQO, 236, 237, 241 

 as fixative, 24, 32, 51, 55, 68, 76, 



78,79, 80, 81, 83, 87, 96, 117, 



142, 204, 205 

 picro-carmine, 294 (see carmine 



picrique) 

 picro-nigrosine, 185 

 Pischinger, 72, 92, 124, 195 

 plasmal, 102 

 plasmalogen, 94, 102 

 Pleiirobrachia, 76 

 polar yellow R, 241 

 Policard, 92, 103 

 polyethylene glycol, 79 

 polyglutamic acid, 58 

 polyglutamine, 58 

 polyglycine, 58 

 polymerization and metachromasy, 



256 

 polymorphs, 263 

 polypeptides, 46 

 polysaccharides, dyeing of, 246 

 ponceau 2R, 183, 236 

 postchroming, 29, 129 

 postosmication, 29, 126, 306 

 potassium acetate, 255 

 alum, 210 

 chlorate, 122 

 potassium dichromate, 24, 32, 63, 



76,78,79,81,83,87, 126, 142, 



204, 256 

 as mordant, 209 

 potassium ferricyanide, 129, 222, 



256, 304 

 hydroxide, 117 



