30 On Staining. 



gland tissue, such as mucous glands in the tongue, it 

 does not, however, stand immersion in spirit well, and 

 the sections require to be deeply stained. It has been 

 recommended for staining amyloid degeneration, but 

 does not excel several other anilines which can be more 

 easily fixed. 



13. Dahlia. Bosanilin, Methylanilin Violet. These 

 three, differing but little in colour, may be con- 

 sidered together ; they can be partially fixed by 

 passing the sections through a 1 per cent, solu- 

 tion of hydrochloric acid, but even then they will 

 not stand prolonged immersion in spirit, and it is 

 better to remove them from the water at once to abso- 

 lute alcohol. The solutions must be rather strong, and 

 the sections well stained before they are removed to the 

 acid solution. 



14. Malachite Green. A very beautiful colour, but 

 will not stand well : it is almost entirely removed by 

 spirit, and is therefore not of much use to the Histolo- 

 gist. 



15. Iodine Green. A darker green than the former, 

 and very durable, standing spirit well and not fading, 

 as far as two years experience goes. It is an invalu- 

 able colouring agent in double staining, as it is not so 

 opaque as anilin blue. Make a saturated solution in 

 water and filter, place a few drops in a watch-glass 

 and dilute : it is very strong, and the section, when 

 taken from spirit, will float on the surface, when it may 

 be seen taking in the colour : if a light stain only is 

 required it will be sufficient to let it remain on the 

 surface ; but if a darker stain is wanted it must be 



