NO. I GROWTH LAYERS IN TREE BRANCHES — CLOCK ET AL, 229 



well as the seven sharp lenses, 7 see remain to represent five years of 

 dated growth. 



TTC 5-9 (table 15, p. 104) was sectioned November 9, 1940; TTC 

 5-10 (table 16, p. 104), February i, 1941 ; TTC 5-1 1 (table 160, be- 

 low), April 5, 1941 ; and TTC 5-12 (table 17, p. 104), May 24, 1941. 



Table 160.— TTC 5-11 

 54 cm. 32 an. 



1936 2 see 



1937 3 see 



I psL 



1938 I see 2 see 



1 psee I psee 



2 sL I sL (the I sL is more like ddw) 



1939 I see 2 see 



2 sL I sL 



1940 I see I see 



1 sL I sL 



2 sL 2 L (lenses fade outward) 



1941 ine L inc L 



Condensed summaries of the four branches are: 



TTC 5-9-a (69 cm.) 

 5 see + I msec + 2 sL + psg — 5 years. 



TTC 5-io-a (53 cm.) 



5 see 4- I msee + 2 sL + i msL + 2 psL + i dL + i s are — 5 years. 



TTC 5-ii-a (54 cm.) 

 8 see + I psee + 7 sL + i psL 4- ine — 5* years. 



TTC 5-i2-a {56 cm.) 



6 see + 3 sL + inc — 3^* years. 



The high degree of multiplicity in the preceding tables and sum- 

 maries is too strikingly obvious to require further comment. 



Momentarily, attention may be directed elsewhere. First, note 

 should be made of the longitudinal change in the content of the annual 

 increments. Some become more complex inward, some more complex 

 outward on the branches in the matter of sharp growth layers which 

 can in no way at present, even under the microscope, be distinguished 

 one from the other as to annual or intra-annual character. Multiplicity 



