Plate 6 



Fig. I. TTC i-ii-b. Portion of same branch section as in figure 2, plate 5, but 



nearly opposite radius. Xylem of 1941-1945. Dating by natural frost effects. 



Compare with figure 2, plate 5, for variations around the circuit, with 



figure I, plate 5, and figure 2, plate 6, and figure i, plate 7, for variations 



along the branch. Partial growth layers and multiplicity. 



1941 : see ; ddw as an incipient growth layer. 



1942 : dL's ; psL , see. 



1943: sL; see. 



1944 : Natural frost spots ; 2 sL as compound lens ; see. 



1945: Natural frost circle; see with ddw. 

 Fig. 2. TTC i-ii-d. Portion of a branch section 134.9 cm. outward on branch 



from figure 2, plate 5, and figure i, plate 6. Xylem of 1941-1945. Dating by 



natural frosts here and elsewhere on circuit. Compare with figure i, plate 7, 



for variations around circuit, with figure 2, plate 5, and figure i, plate 6, 



and figure i, plate 5, for variations along branch. Lensing and weak annual 



boundaries. 



1941 : see with ddw and irregular outer margin. 



1942 : see with weak dw. 



1943 : s ^L; see with very thin, weak dw after separation of ^L. 



1944: Spots of natural frost efi^ects ; sL ; s ;jL difi'using into an incipient 

 "invisible" gl ; see. 



1945 : Natural frost circle ; see with irregular dw. 



