DETECTION AND IDENTIFICATION 61 



alcohol in order for 5 minutes each. Then if counter- 

 staining is desired, dip in 1% eosin in 95% alcohol for a 

 few seconds, and then transfer the smears to two changes 

 of plain 95% alcohol, two changes of absolute alcohol, and 

 finally two changes of xylol. The smears can now be 

 mounted one bv one in a drop of Canada balsam-xylol 

 which is placed in the center of a slide. The technique 

 involved is simple and with a little practice, satisfactory 

 smears can be prepared. Before examining the slides under 

 the microscope they should be placed in a drying oven 

 at about 60 °C. for a little while. As in the case of fresh 

 smears, microscopical examination of permanent prep- 

 aration should be done as far as possible under low mag- 

 nifications. 



