NO. I GROWTH LAYERS IN TREE BRANCHES — CLOCK ET AL. 23I 



Branch TTC 12-10 (table 19, p. 105) was cut off April 21, 1940. 

 Its summary for sections a (66 cm.) reads: 



3 see + I msce + 2 psce + 4 dee + inc L's — 3* years. 



As the table shows, there is not one see for each year. The growth for 

 1940 in sections a consists of one long and two short incomplete lenses, 

 whereas in b (34.5 cm.) it is entire but incomplete, around the circuit. 

 In most cases where branches have been cut off before the first growth 

 layer of the season has been completed, we have found that the cam- 

 bium apparently begins to divide initially at one or several points, 

 spreading so as to create lenses which finally unite to form an entire 

 growth layer. This appears to be true transversely as well as longi- 

 tudinally. 



Branch TTC 12-11 (table 161) was cut off June 29, 1940. 



Table 161.— TTC 12-11 



63 cm. 

 1932 I see 



1933 2 see 



2 psce 

 2 dee 



1934 2 see 



I sL 



I d arc 

 ddw 



1935 3 see 



I sL 



1936 I see 



I msce 



1937 2 see 



I sL 

 I dL 



1938 2 see 



I psL 

 I d iL 



1939 I see 



1940 I see 



psg 



The summary for branch TTC 12- 11 reads: 



IS see + I msce + 2 psce 4- 2 dee 4-3 sL 4- 1 psL 4- i dL 4- 1 d iL 4- 

 I d arc 4- I ddw 4- psg— 8* years. 



