212 Silver Impregnation II (chap. 15) 



Warren's {1944) modification: 



Warren writes that large pieces of muscle give better results than 

 small ones because in the latter the muscle fibers may become too 

 dark. He removed 5 or 6 ribs from a rabbit with the muscle and ten- 

 dons intact. In this case the timing in solutions will have to be ex- 

 tended. 



procedure: 



1. Treat with citric acid: 2 hours. 



2. Wash in 2 changes of distilled water: 5 minutes each. 

 ?>. Transfer to gold chloride: 2 hours. 



4. Transfer to formic acid: 24 hours; change solution at end of first 

 12 hours. 



5. Wash in 3 changes of distilled water: 5 minutes each. 



6. Treat Avith pure glycerine: 24 hours, then change to a fresh solu- 

 tion. 



7. To mount: cut the muscle from between the ribs, cutting close to 

 the bone. Cut the muscle in small strips 5 mm. long. Keep strips 

 stored in the glycerine while preparing them for mounting. Pre- 

 pare thin mounts as in technic above. 



comments: 



The author has not used this method, but makes the following sug- 

 gestion: to prevent swelling of the tissue, do not go directly from 

 water (step 5) into glycerine (step 6). First treat with 50% alcohol- 

 glycerine (1:1) several hours or overnight, then proceed with step 6. 



Myelin 



Luxol Fast Blue (margolis and pickett, 1956) S 

 fixation: any good general fixative. 



embedding: paraffin method. 



solutions: 



Luxol fast blue: 



Luxol fast blue MBSN ~ 0.1 gm. 



95% alcohol 100.0 ml. 



acetic acid, 10% aqueous 0.5 ml. 



Keeps indefinitely. 



- E. 1. I')iiI'ont de Nemours and Company. 



