466 



hid ex 



Picric arid: in fixatives, 9; destaining \vith, 



134; staining with, 165. 166, 230 

 Picro-Gomori trichrome method, 159 

 Picro-ponceau staining ("A'an Gieson). 165, 



166 

 Pigments: description, 232; removal of, 213 

 Pike oil, 44 

 Pinacyanole staining: freezing method, 67; 



sex chromatin, 362 

 Pituitarv: discussion, 283; methods for, 284 

 Planaria, fixation, 373 

 Plasma cells, definition, I 16 

 Plastic embedding, see Polyester resin 



method 

 Plastic mounts, 394 

 Platelets, staining, 220 

 Platyhelminths: fixation, 373; staining, 377, 



382, 384 

 Pointer for eyepiece, 94 

 Polarizing microscope, 98 

 Pollak's rapid trichrome stain, 155 

 Polychroming, 110 



Polvester resin embedding method, 85 

 Polyethylene glycol, see Water soluble 



waxes 

 Poirrier's blue, formula and use, 326 

 Pohmorphs, see Leukocytes 

 Polysaccharides, DNA and proteins triple 



stain, 302 

 Polyvinyl alcohol (PVA) mounting medium, 



120 

 Ponceau de xylidine, in Masson stain, 152, 



154 

 Ponceau 2R, in trichrome stain, 155, 286 

 Ponceau S, staining, 165, 166 

 Porifera, fixation, 372 

 Post fixation treatments: chromatization, 



23; decalcification, 24; deformalization, 



24; mercuric chloride removal, 9, 12, 24; 



washing, 12 

 Potassium dichromate: chromatization, 23; 



in fixatives, 9 

 Potassium: ferricyanide, 235; ferrocyanide, 



233, 234 

 Potassium permanganate for electron mi- 

 croscopy, 400 

 Precipitate, mercuric chloride elimination, 



9, 12 

 Progressive staining, 108 

 Propane-isopentane, in ice-solveni method, 



337 

 Propylene glycol, use in ice-sohent method, 



337 

 Protargol, 203 



Protein staining, 246; with DNA and poly- 

 saccharides, 302 

 Protozoa: fixation, 384; co\er glass mount- 

 ing, 385; staining, 385 



Protozoa, intestinal: smear technics, 386: 



section tcchnic. 390 

 Prussian blue, see Berlin blue 

 Putt's eosin, 129 

 PVA (polyvinvl alcohol) mounting medium, 



120, 355 

 Pyridine silver impregnation, 200 

 Pvronin methvl green for nucleic acids, 297 

 P\ rox\lin, see Nitrocellulose 



Quad stain, Kornhaiiser's, 161 

 Quartz microscope accessories, 100 



Quenching, 338 



Radioautography, 395 



Ramon y Cajal's: gold chloride for astro- 

 cytes, 193; for neurofibrils, 197; pyridine 

 silver, 200; silver impregnation methods, 

 176 



Rapid method. Lawless, for intestinal pro- 

 tozoa, 389 



Rapid staining method, biopsies, 67 



Rays, ordinary and extraordinary, 99 



Razor blade holder, Spencer (American 

 Optical Company), 49 



Reclaiming stored gross specimens, 426 



Red blood cells, see Erythrocytes 



Refractive index, 88 



Regaud's fixative, 20 



Regressive staining, 108 



Removal of pigments, 243 



Removing laboratory stains, 428 



Resin mounts: drying, 118; mounting cover 

 glass, 115, 122 



Resins, s)nthetic, 116 



Resorcin-fuchsin: Weigert-Hart's, 162; in 

 pentachrome stain, 162 



Restoration of slides: chromosome prepara- 

 tions, 370; faded tissue slides, 424; blood 

 smears, 221 



Reticular fibers (reticulum): definition, 

 145; silver impregnation, 179; staining, 

 150, 162, 165 



Reticulum, combined with collagen and 

 elastin staining, 186 



Rhodacyan method for pituitary, 289 



Rickettsia staining, 324 



Ringer's solution, 411 



Ringing cements, 123 



Ringing cover glasses, 123 



Rio Hortega silver methods, see Del Rio 

 Hortega 



RNA, ribose nucleic acid: methods for, 297, 

 360; removal, 300 



Romanowsky stains, 110 



Rosiu (Colophonium) solution, 225 



Rossman's fixative, 20 



Rotary microtome, 43, 52 



Rolifeis, anesthetizing, 372 



