262 LEPROSY. 



up the basic aniline stains rather more readily than tubercle 

 bacilli, but in order to stain them deeply a powerful stain, 

 such as carbol-fuchsin, is necessary. When stained, they 

 strongly resist decolorising, though they are more easily 

 decolorised than tubercle bacilli. The best method is to 

 stain with carbol-fuchsin as for tubercle bacilli, but to use a 



FIG. 70. Superficial part of leprous skin; the cells of the granulation 

 tissue appear as dark patches, owing to the deeply-stained bacilli in 

 their interior. In the upper part a process of epithelium is seen. 



Paraffin section ; stained with carbol-fuchsin and Bismarck-brown, 

 x 500. 



weaker solution of sulphuric acid, say 5 per cent, in de- 

 colorising ; in the case of films and thin sections, decolor- 

 ising with such a solution for fifteen seconds is usually 

 sufficient. Thereafter the tissues are coloured by a contrast 

 stain, such as a watery solution of methylene-blue (vide 

 p. 113). The bacilli are also readily stained by Gram's 



