SMITHSONIAN MISCELLANEOUS COLLECTIONS 



VOL. 140, NO. 1, PLATE 26 



XS'C Q-i-a. Branch section of Cuprcssus arizouica. cut May 2^, 1941. Xylem of 

 1938-1941. Longitudinal variation of intra-annual contacts, plates 26, 27, and 

 28, figure I ; growth rhythms. 

 1938: see at center. 

 1939 : Multiple diffuse dw's ; msce. 

 1940: Multiple diffuse dw's ; nisce which changes to psce 15 cm. outward and 



to dee 25 cm. outward on the branch ; see. 

 1941 : inc. 



