STAINING, PRACTICAL AND THEORETICAL 



Solutions required: 

 A. Alizarin Red, S, i% aqueous 



Technique: 



Fix in 95% alcohol for at least two weeks after making a midline 

 abdominal incision to allow penetration of the fixative. 



1. Rinse in tap water. 



2. Immerse for at least four weeks in 1% potass, carbonate. 



3. Immerse for at least ten days in 1% aqueous potass, hydrox- 

 ide until the bones are clearly visible through the soft tissue. 



Note: Formalin-fixed specimens require four to six weeks in 

 I % potass, hydroxide. Should the specimen become too soft it 

 may be hardened by immersing for twelve to twenty-four hours 

 in a mixture consisting of equal volumes of glycerin, water and 

 95% alcohol before returning to the clearing solution. Potass, 

 hydroxide 0-5% may be used during the last few days of the 

 clearing. 



4. Wash twenty-four hours in running tap water. 



5. Stain one-half to six hours, according to the size of the speci- 

 men, in Solution A. 



6. Wash for thirty minutes in running tap water. 



7. Decolorize seven to fourteen days in Solution B. 



8. Mount in a glass frame and dehydrate by passing slowly 

 through alcohol-glycerin-water mixtures beginning with the pro- 

 portions 1:2:7 and then in succession 2:2:6, 3:3:4, 4:4:2; 

 and finally equal parts of alcohol and glycerin only. 



9. Seal in the usual glycerin-alcohol mixture. 



References : 



Dawson, A. B. (1926). 



Richmond, G. W. & Bennett, L. (1938). 



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