EXPERIMENTAL EQUIPMENT AND PRCXIEDURES 17 



e. Kleinberg's picro-sulphuric - tor polar bodies and spindles (McClung). 



Water 200 vols. 



Cone. H2SO4 2 vols. 



Picric acid - to saturation 



f. Chrom-acetic fixative - excellent lor cytological studies of amphibian egg and 

 embryos: 



Chromic acid 10% 25 pts. 



Glacial acetic acid 10 pts. 



Sat. aq. picric acid 100 pts. 



g. Gilson's fixative - Carnoy & Lebrun, 1897: La Cellule 12: 



Nitric acid - 80% 1 5 cc. 



Glacial acetic acid 4 cc. 



Corrosive sublimate 20 grams 



Alcohol 80% 100 cc. 



h. Gatenby's fluid: 



K. Bichromate - 2% aqueous 100 cc. 



Chromic acid 1% 100 cc. 



Nitric acid 6 cc. 



i. Stockard's solution - for fish embryos: 



Formalin 5 pts. 



Glacial acetic 4 pts. 



Glycerine 6 pts. 



Water 85 pts. 



j. Acetic alcohol : 



Absolute alcohol 90 cc. 



Glacial acetic 10 cc. 



k. Corrosive acetic : 



HgCl2 5 gr. 



Glacial acetic 10 cc. 



Water 90 cc. 



1. Formalin - two concentrations should be available, 10% and 4%. 



1 1 . Bleaching Agents : 



a. Javelle water - potassium hypochlorite. 



b. Mayer's chlorine - to be made up just before use 



(1) Place few crystals potassium chlorate in vial. 



(2) Add 2-3 drops HCl. 



(3) When green chlorine fumes evolve, add 2-10 cc. of 70% alcohol. 



(4) Transfer specimens from pure 70% alcohol to this mixture until bleached. 



c. Ammoniated alcohol - 2% NH4OH in 70% alcohol to decolorize picric acid stain. 



CYTOPLASMIC STAINS 



a. Eosin - 0. 5% in 95% alcohol. 



b. Light green (Grlibler's) - 0. 5% in 95% alcohol. 



c. Fast green (Nat. Aniline Co. , N. G. f. 3) 0. 5% in 95% alcohol. 



d. Safranin O (Nat. Aniline Co. , N. S. -10) 1% in aniline water. 



e. Orange G - sat. in clove oil. 



f. Masson stains (A, B, C. ) Excellent for cell types (pituitary). 



g. Alizarine S - (used in Spaltoholz technique). 



