228 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I4O 



TTC 5-2-a (193 5- 1939) 

 7 see 4- 2 sL + 2 psL + I dL + I s arc— 5 years. 



Here, there are nine wholly sharp contacts plus three partially 

 sharp. 



TTC 5-3-a (i935-mo) 

 5 see + 6 msce + 3 sL + 2 msL + i dL + i s arc— 5* years.^ 



The plus sign is added because the sections were cut June 2^, 1940, 

 by which date i sce+i sL4-i dL had been formed. At first sight it 

 seems that there might be i see for each year, but this is not true. The 

 increment for 1936 contains 3 msce+i sL+i msL and that for 1937, 

 3 msce + 1 msL+i s arc, whereas 1938 has 2 see only. Thus in TTC 

 5-3 the best developed and most sharply defined growth layers con- 

 stitute neither the principal growth layers in all cases nor the outer 

 boundaries of the annuals. 



TTC 5-4-a (1933- 1940) 

 9 see 4- 4 sL 4- I dL — 7* years. (See table 10, p. 103.) 



The sections were cut July 17, 1940, by which time i see had been 

 formed. 



TTC 5-6-a {1936-1940) 

 7 see 4- 1 msce 4- i psce 4- 1 sL 4- 2 psL 4- 2 s arcs 4- i inc L — 4* years. 



The sections were cut August 17, 1940, by which time i sce+i 

 psL4-inc L had been formed. The increment for 1937 contains 2 see 

 4-1 msce 4- 1 psL4-i s arc. On one part of the sections, over a dis- 

 tance of more than 90 degrees, 1937 has four sharply bordered growth 

 layers and, with the lens included, five sharp margins. 



TTC 5-8-a (1936- 1940) 

 7 see 4- I psce 4- 7 sL 4- i psL 4-1 s arc 4- psg — S years. 



The sections were cut September 28, 1940, and by that time of year 

 I see 4- 2 sL4-psg had been formed. No doubt the psg is actual post- 

 seasonal growth. It decreases outward on the branch. With 2 see 

 4-3 sL, 1937 has five sharp growth layers on certain radii. With i 

 see 4- 1 psce 4- 1 psL4-i s arc, 1938 has three sharp growth layers on 

 certain radii. Even if all partially sharp growth layers be neglected as 



s A plus sign (4-) after the number of years means that a branch was cut ofif 

 before the end of the growing season which therefore is not recorded as a full 

 year. 



