STAINING PROPERTIES 409 



the fungi and the tissue cells surrounding them have undergone 

 calcification, and the rosette appearance is then not so characteristic ; 

 it may, however, be brought out by the addition of dilute acetic acid, 

 which will dissolve the lime salts. 



Staining Properties. It is unnecessary and in fact disadvantageous 

 to attempt to prepare stained cover-glass preparations, because in 

 preparing a thin spread the characteristic rosette form is destroyed. 

 To study the finer structures of the actinomyces rosettes it is necessary 

 to embed and section tissues containing them. The sections may be 

 stained with hematoxylin and eosin, or, better still, by one of the 

 following methods : 



SCHLEGEL'S METHOD. 1. Stain celloidin sections for four to five 

 hours in the incubator in a strong alcoholic solution of eosin the 

 alcohol-soluble eosin must be used, not the water soluble eosin. 



2. Wash rapidly in 90 per cent, alcohol. 



3. Stain for five to ten minutes in watery hematoxylin solution. 



4. Wash in water. 



5. Wash rapidly in alcohol. 



6. Lift on slide with lifter. 



7. Dry with filter paper. 



8. Pour on some xylol or carbol-xylol to clear. 



9. Mount in Canada balsam. 



WEIGERT'S METHOD. 1. Stain sections well with borax-alum, or 

 lithium carmin. Lithium carmin generally stains in twenty to thirty 

 minutes; the other carmins must act for twenty-four hours. 



2. Wash in acidulated alcohol (70 per cent, alcohol, 100 parts -f 

 HC1 ^ per cent). 



3. Wash in 95 per cent, alcohol. 



4. Stain in anilin-water gentian violet for five to twenty minutes. 



5. Wash in normal salt solution. 



6. Gram's decolorizing solution a few seconds (iodin, 1 part; iodide 

 of potash, 2 parts; water, 300 parts). 



7. Decolorize in anilin-oil-xylol. 



8. Wash in several changes of pure xylol. 



9. Mount in Canada balsam. 



MALLORY'S METHOD. 1. Stain sections for at least ten minutes 

 in a saturated solution of water-soluble eosin. 1 



2. Wash rapidly in water. 



3. Stain for a few minutes in anilin-water gentian violet. 



4. Wash in normal salt solution. 



5. Iodin solution (iodine, 1 part; iodide of potash, 2 parts; water, 

 100 parts). 



6. Wash in water, lift on slide with a lifter, dry with filter paper. 



7. Decolorize on slide with anilin oil, several changes. 



8. Clear with xylol several changes. 



9. Mount in Canada balsam. 



1 The section may also first be stained with alum carmin, but not very deeply. 



