l82 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I40 



first tip flush of 1939, and those at 4 cm. were taken from the fifth 

 or outer tip flush. 



Table 138.— YCt j-i Table 139.— FO 3-2 



9.5 cm. 6 cm. 



1938-1940 11-13 see 1938-1940 11+ see 



L's L's 



psg psg 



The sections of YCt 3-1 (table 138) were taken 9.5 cm. inward 

 from the outer end of 1938 tip flush. 



The sections of YCt 3-2 (table 139) were taken 6 cm. inward from 

 the outer end of 1938 tip flush. Some of the lenses are compound. 

 Branches YCt 3-1 and 3-2 possess remarkable multiplicity, a multi- 

 plicity which is not too surprising in the environment of the Experi- 

 ment Station at Yuma, Ariz. 



Table 140.— YCt 4-1 



12 cm. 



1937-1940 16 see 



L's 



psg 



The sections of YCt 4-1 (table 140) were cut 12 cm. inward from 

 the outer end of 1937 tip flush. Diameter growth was proceeding rap- 

 idly when the branch was cut off November 26, 1940. 



Table 141. — YCt 4-2 



8 cm. 



1937 3 see 



1-2 L 



1938 2 see 



1939 2 see 



2-4 L 



1940 5 see 



L's 

 psg 



Annual increments in YCt 4-2 (table 141) were tentatively dis- 

 tinguished on a color basis ; there is no assurance of accuracy. 

 Growth over a period of four years included 12 sharp, complete, en- 

 tire growth layers and an additional number of lenses. 



