Golgi Apl)nratus and Mitochondria 205 



4. Flood with toluidine blue (), 0.5% (0.5 gm./lOO ml. water): 1-2 

 minutes (see comments below). 



5. Rinse in distilled water. 



6. Cover with aurantia, 0.5% (0.5 om./lOO ml. 70%, alcohol): 20-40 

 seconds. 



7. Differentiate in 95% alcohol. 



8. Dehydrate, absolute alcohol, clear, and mount. 



RESULT.S: 



mitochondria — red 



nuclei — blue 



cytoplasm — greenish yellow 



comments: 



If sections are too S[;ed, increase the time in toluidine blue. If they 

 remain too blue, increase the time in aurantia. 



Benda's staining solution is sometimes used in place of Altmann's 

 fuchsin. 



solution: 



crystal violet saturated in 70%, alcohol 1 part. 



absolute alcohol 1 part. 



aniline saturated in water 2 parts. 



Dilute ^vith equal parts of distilled water. 

 Use like Altmann's fuchsin. 



procedure: 



(a) Blot and immerse in dilute acetic acid (30 ml./70 ml. water): 1 

 minute. 



(b) Blot, immerse in absolute alcohol initil only a little stain comes 

 out. 



(c) Clear and mount. 



results: 



mitochondria — deep violet 

 backo round — rose 



Iron Hematoxylin also can be used for mitochondria. Best fixative 

 is Regaiid, and mordant in .3% potassium dichromate: 7 days. Use 

 the long method of staining: overnight in iron alum and overnight 

 in hematoxylin. The method is not as specific as Altmann or Benda; 

 other granules also stain. 



