LBPEOSY BACILLTJS IN SECTIONS. 545 



washed in water -till they acquire the characteristic bluish 

 tint. They are now placed in Ziehl's solution for about 15 

 minutes, and then in the anilin hydrochloride solution for a 

 few seconds. They are now washed in 60 per cent, alcohol 

 till the color ceases to be given off, after which they are 

 dehydrated in absolute alcohol, cleared in xylol, and 

 mounted in balsam. ' 



The carbolic fuchsin may be replaced by anilin- water 

 fuchsin or gentian violet, as employed in the original 

 method of Ehrlich. 



The two methods for staining tubercle bacilli may be 

 summarized as follows : 



1st method. Snd method. 



Carbolic fuchsin (warm, 15-30 Hematein (2 min.). 



min.). Wash, and develop in water. 



Wash in water. Carbolic fuchsin (15 min.). 



60 per cent, alcohol (1-2 min.). Anilin hydrochloride (few sec). 



Ebner's solution {% min.). 60 per Cent, alcohol. 



60 per cent, alcohol (1-2 min.). Absolute alcohol. 

 Loffler's methylene blue i}i min.). Xylol. 



Wash in water. Canada balsam. 

 Absolute alcohol (20 sec). 

 Xylol. 

 Canada balsam. 



LEPROSY BACILLUS. 



In sections made from fresh tissue, the leprosy bacillus 

 can be stained by the method employed for detecting the 

 tubercle bacillus. But, a§ stated above, this staining pe- 

 culiarity is lost, after a time, if ^he tissue is preserved in 

 alcohol. Although the above method fails, yet the leprosy 

 bacillus can be demonstrated easily in such tissue on stain- 

 ing by Gram's method (p. 541). Under these conditions, ex- 

 cellent results can be obtained by leaving the sections in 

 anilin- water gentian violet over night. 



The leprosy bacillus is distinguished from the tubercle 

 bacillus by being easily stained with the ordinary dilute 



35 



