Stains and Staining 63 



Mix equal parts of A and B. Transfer to the stain from water. 

 The proper time must be determined by experiment. For a trial, 

 24 hours might be recommended. Transfer from the stain directly 

 to solution C and from C to xylol. 



Another formula: 



A. Acid fuchsin . 5 g. 



B. Iodine green . 5 g. 



Mix a pipette full of A with a pipette full of B; stain 2 to 8 

 minutes; transfer to 85 per cent or 95 per cent alcohol, dehydrate 

 rapidly, clear in xylol, and mount in balsam. Both these formulae 

 are good for mitosis. 



Acid Fuchsin and Methyl Green. Both may be used in 1 per 

 cent aqueous solutions. 



For mitotic figures, stain in green for about an hour, wash in 

 water or alcohol until the green is extracted from the spindle, and 

 then stain for about one minute in the fuchsin. Dehydrate in 95 

 and 100 per cent alcohol, clear in xylol or clove oil, and mount in 

 balsam. If the green washes out, stain longer; if it is not readily 

 extracted from the spindle, shorten the period. If the fuchsin stains 

 the chromosomes, shorten the period, and lengthen it if the fuchsin 

 washes out from the spindle. The chromosomes should take a 

 brilliant green and the spindle a bright red. 



Delafield's Haematoxylin and Erythrosin. Stain first in the 

 haematoxylin, and after that stain is satisfactory, stain for 30 seconds 

 or 1 minute in erythrosin. This is a good combination, and, for 

 most plant structures, gives a far better differentiation than the 

 traditional haematoxylin and eosin, since the erythrosin has all the 

 advantages of the eosin and is more transparent. Orange G is also 

 a good stain to use with Delafield's haematoxylin. 



Directions for staining in safranin and Delafield's haematoxylin 

 are given in the chapter on "Freehand Sections" (chap. vi). 



Haidenhain's Iron-Haematoxylin and Orange G.--This haema- 

 toxylin is very satisfactory when used alone. A light staining in 

 orange G, however, sometimes improves the mount. After the last 

 washing in water, stain for about 30 seconds in orange G. Eosin, 

 erythrosin, and nearly all plasma stains fail to increase the effect of a 

 good stain in iron-haematoxylin. 



