SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 140, NO. 1, PLATE 27 



XSC g-i-b. Sectiun taken 15 cm. outward on branch section shown on plate 26. 

 Xylem of 1939-1941. Intra-annual psce of 1940 is msce 15 cm. inward ( pL 26) 

 and dee 10 cm. outward on branch (pi. 28, fig. i) ; growth rhythms. 

 1939 : dee ; msce. Cell columns bent both clockwise and counterclockwise. 



Curtainlike dw ; multiple bands of diffuse to definite dw ; psce which 

 is msce on plate 26; mostly dee but partly sharp dw near outer 

 part of increment (faint in pi. 26 ) ; msec; si. which is present as 

 expanded dw in plate 26. 

 inc. Frozen artificially May 9, 1951. 

 In passing outw^ard from sections o to b. the axis of the diffuse margin has 

 rotated clockwise and the axis of the outer lens of 1940 has rotated counter- 

 clockwise. 



1940: 



1941 



