396 



Bulletin 258. 



"a •J4 S2 









«0 



s 



to 



a 



8 

 o 

 </> 

 o 



lO 



a 



K 



-Si 









>- CI 



S 

 .s "^ -s? 



Is- '^ 



C3 - -Si 



(J 



■13 





6jO 



a 



a 



S 



a ex, ^' 



-a 



a • 



to -Q 



a ° 



to 



CO 



O O 



PC4 



