756 HISTOLOGIG TECHNIG 



Orange G 2 grm. 



Methyl green 1 grm. 



Mix the fluids and dissolve the dyes in the order given. 

 When used for staining sections., either of these formulas should be 

 diluted with five to ten volumes of the following mixture : 



Glycerin 10 c.c. 



Distilled water 15 c.c. 



95 per cent, alcohol 25 c.c. 



1. Stain five to ten minutes in the diluted solution. (Use full 

 strength for blood smears.) 



2. Einse in water. 



3. Dehydrate in absolute alcohol. (Smears are dried in the air.) 



4. Clear and mount. 



The best results are obtained with tissues fixed in a sublimate mix- 

 ture. It is a delicate cytologic stain, and is serviceable in differentiating 

 between chromatin (chromosomes) and plastin (plasmosomes and linin) ; 

 also in differentiating cytoplasmic granules. Sections should not be over 

 3 p in thickness. The stain is more or less capricious. 



Auerbach's Fuchsin-Methyl-Green Stain. This stain does well 

 only after a sublimate fixative. It is serviceable in cytologic work for 

 differentiating between 'active' and 'resting 5 chromatin. When suc- 

 cessfully manipulated it stains the chromosomes green and the plasmo- 

 somes and linin red. 



Keep in separate bottles the following stock solutions: 



I. Acid fuchsin 1 part, distilled water 1,000 parts. 

 II. Methyl green 1 part, distilled water 1,000 parts. 



Mix when ready to use in the following proportions : 



2 parts of I, acidulating every 50 c.c. with 1 drop of a 10 per 

 cent, solution of glacial acetic acid. 



3 or 4 parts of II. 



Fix tissues (e.g., insect testes, etc.) in the sublimate acetic mixture, 

 transfer direct to 80 per cent, alcohol (removing the mercury with tinc- 

 ture of iodin), dehydrate, and embed in paraffin. Sections should not 

 be cut over 3 p thick. 



Stain for fifteen minutes, and pass directly to 95 per cent, alcohol. 

 When the green stain no longer leaves the sections in clouds, pass 



