28 



BULLETIN 948, U. S. DEPARTMENT OF AGRICULTURE. 



© 



< 



S» 



z 



rQ 



< 



„ 



\A 





a 



%> 



< 



s 





T3 





s 





















CO 





!£ 



1 -* r- oo 





CI 



-V 























• 



■a 















io®ro 





CO 























1 











CN 



c 



OO OS 



- 



c 

























s 









































s 



6 







































lO 





ft, 







































1 











^ 



-* 



NO00 



y. 



o 





















1 



d 











CO 



CO 



O CO CN 



CO CO CO 



X 



CC 























O 



s 







































o> 



o 











































a, 















ll 



































^ 





COHCO 





OO 























as 











































oS" 











































W P< 











































« 





m 



IG 





CN 



c 



U3 









lO 





CN 







CN 









"3 







r~ 



I- 





-: 



CC 











1C 























CO 



- 







c 



o 









c 





en 







a> 











s 









































rt 



o 







































to 





ft. 







































l 





lO 



IT 





Tj 



-* 



J* 









-V 





_ 







rt 







3 



d 





00 



CC 





CO 



CC 

 CC 



CO 









c 



CO 





CO 

 CO 







CO 

 CO 







OS 



o 













































ft, 











































(N 



CN 









-* 









■* 





rt 







rt 









as 











































03-"-! 











































CO Ph 











































1° 







t~ 









CO 





00 



tc 



CN 









CN 









3 







c 









CN 







CC 



O 









o 













c 









o 





c 



o 



















3 ~ 







































c -1 



































a 

 o 



t^- 





ft 



— 



- 





































































'a w 















rH 





■* 



Tj 



cs> 









C35 





03 



3 

















CO 





CO 













T-i 





CO 



d 



eco 







PC 









CO 





CO 



CC 



CO 









CO 





Pi 



O 



CO 



O 



o 

 ft 



































o 





9 S 



CO "ft 



" 















"* 







ir. 



CM 









CN 









■§ 



S 



Oi 00 





IOCC 



f- 



O) fH N »0 I s - 



oc 





NMOh 



ca 









"J3 



CO o 



cr 



ooc 





COlOCf)iO"+ 







Oi <M Ol n 



o> 









coo 



— 



cor- 



c 



O O Oi o o 



c 





oiooa 



OS 









1 



s 



























o 

























CO 





ft 

























i 



oooo 



CC 



rHCN 



CN 



O1-+00-H O 



>r 





CO CC CO o 



00 















Tt< t 



-t 



O CN COCN O 









r-t t-ho a 



o 







t~ 





coco 



f 



CO c- 



c<- 



CO CO CO CO c 







CO CO CO CN 



CO 









o 



s 

























01 



o 





























ft 























, 





CDr-H 



t- 





CM 



lO'+rHcOr- 



~f 





rtHiou - 



CN 









as 



03 —< 













»H 



o 





rH rH 



CO 



































oa a 































CC 











COCN -rF^O -t 



cr 



*H o 



00 CC 



CO 









"3 

 cs 





cc 









HmiQr-*CC 





o r^ 



cn zr 











5 



c 









o oooc 



b 



cso 



oc 



O 









3 -• -» 





























s 



o r ~ l *~ l 



























O 



ft 



























42 co »o 





X 









lO ,_( IO CO CN 



IT 



ION 



-t< r^ 









3 



Oi 





^5 CO »o 













O r-t 050CC 



~ 



00 Oi 



t^-cC 



CO 









S CN CN 



? 











CO CO CN CO CN 



CN 



CN CN 



CI o 



CN 







o 



S 































ft 



























CO CO 



CM 



oc 









OiCD 00"^ c- 



c 



t~lO 



■-lev 



>o 









as 















'"' 









rH 









o3---: 































go P 

























) 





a 





i 



3 















oc 

























•r 





60 











c 







a 













y 

















2 i 



o 









c 







c 













c 













o 





03 -o 



s 



ft 







































1-1 

















































^"3 





1 



3 









-t 







cr 













c 













o 





^.2 



d 

 O 









c 

 cv 







c- 





























A 



o 



ft 











































fmM 













ot 







Tt 

























o 





|is 































01 













>o 





1 













































SSI 















































lc 













































« 





























































































"5 















































o 















































a 















































■eJ 















































a 



C3 













a 



















a 













CD 





CD 



Ss 





fe 



c 



CC 





feh 





& 



fe^ 



CJ) 

 03 



>> 





■-■ a 2 a \ 



■> c 



il 



d ®"c 







■■i|iii 



■> a 



■a & « o 2 1 



1 CO 



d 

 3 



o 

 O 





< 



«* 



5 



3 





3 So 55,2 





£ ft t: 

















03« C 















o 











o 







o 













o 



















