COLLECTION OF SECTIONS. 
Suro tcstse ab 
| eo oi 
ut fat Hu HAN) 
( o5mm. 
tip tt | AN fy } ia i 
TAR aR 
te 
—# 
3 
UY dP 
Fig. 3.—Annual growth of trees at Flagstaff from 1385 to 1906, A. D. 
