EXAMINATION OF BACTERIA, DIAGNOSIS, ETC. 31 



If the specimen to be examined be tissue, a compli- 

 cated process of hardening and embedding in paraffin or 

 celloidin must be carried out, after which sections or 

 slices so thin as to be translucent are cut from the speci- 

 men, the paraffin or celloidin dissolved out, and the sec- 

 tion stained by immersion in solutions of certain dyes. 

 It is then mounted in Canada balsam and examined in 

 the usual way. 



