22 



Journal of Applied Microscopy. 



W 



l-H 



o 



O 



< . 

 < 



u 



S 



W =: 



^ a 



< ^ 

 pj U 

 > 



H 



H 



W 

 W 



cu 

 w 





Q 



Z 

 < 



> 



o 

 o 



_l 



o 

 > 



cc 



UJ 



Q 

 z 

 < 



^< 

 IQ- 



^1 



O 



CO 



O 

 cc 

 o 





O bo 



■ir; -"h 



m .S 



.S S 



S S 



S P^ 



=2 o 



d ft 





>. td 



fl O £ ( 





5^P 



11 I 



< » 





