hours, are then washed in Weigert's differentiating fluid ; 



Borax, ....... .2 grms. 



Potassium ferricyanide, . . . . . 2.5 grms. 



Distilled water, . ; . . . . . 100 c. c. 



The sections remain in the differentiating fluid until 

 the gray matter has a brownish-yellow, and the white a 

 bluish-black color. Sections are then washed in tap 

 water for several hours, dehydrated in alcohol, and cleared 

 in the following clearing fluid (Weigert's) : 



Carbolic acid crystals ... 1 part. 

 Xylol v 3 parts. 



The. sections may then be mounted in balsam. 

 This method has been variously modified ; two such 

 modifications are here given. 



Pal's Method. 



Prepare and cut sections as for Weigert's stain. Stain 

 in Weigert's hsematoxylin solution, after staining wash the 

 sections in water to'which a trace of lithium carbonate has 

 been added. The sections are then placed in a ^% aqueous 

 Solution of permanganate of potash in which they remain 

 20 to 30 seconds, are then rinsed in distilled water, and 

 differentiated in the following solution : 



Oxalic acid ... . . . 1 grm. 



Potassium sulphite (K 2 So 3 ) . . 1 grm. 



Distilled water . . . .200 c. c. 



They remain in this solution for i to 1 minute, or until 

 the gray matter has assumed a yellowish color, are then 

 washed in water, dehydrated, cleared in Weigert's clearing 

 fluid, and mounted in balsam. 



Benda's Method. 



Bemla's modification is usually followed in this laboratory. 

 Harden tissues in Miiller's fluid. 



I 



Embed in celloidin. 



\, 



Sections are placed for 12 to 21 hours in the following solution : 

 Liquor ferri ter stilphatis . * 1 part. 

 Distilled water . . . . 2 parts. 



