26 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Ill 



August during the period 1909-1941 are given for the several stations. 

 These average departures are noticeably less than the comparable 

 values for the growth layers of the Holman Pass collection. In the 

 second portion of the table the average departures of the period 

 1 850- 1 897 are distinctly higher than those of the period 1 898-1 941. 

 The contrast between the two periods stands thus : a lower average 



Table 14. — Hohnan Pass tree growth and Santa Fe rainfall — characteristics 



1850-1897 1898-1941 



Average magnitude 



Rainfall (inches) 6.34 6.74 



Growth layers (mm.) 



G 10 1.53 170 



II 2.26 1.96 



7 (restricted) 1.99 1.83 



Average variation 



Rainfall 0.42 0.33 



Growth layers 



G 10 0.26 0.40 



II 0.38 0.27 



7 (restricted) 0.33 0.32 



Average departure 



Rainfall 0.33 0.22 



Growth layers 



G 10 0.32 0.36 



II 0.34 0.30 



7 (restricted) 0.35 0.31 



Average departure from mean variation 



Rainfall 0.25 0.22 



Growth layers 



G 10 0.132 0.148 



II 0.204 0.118 



7 (restricted) 0.130 o.ioS 



rainfall during the earlier period is accompanied by a higher average 

 variation and by a higher average departure. On the whole, such 

 characteristics are to be expected.^" 



There remains, then, a comparison between the characteristics of 

 the growth layers and those of rainfall for which the records of Santa 

 Fe are used because of their length and continuity. Table 14 makes 



^^ Mixer, C. A., The rainfall year, Bull. Amer. Meteor. Soc, vol. 15, pp. 22-23, 

 1934; Williamson and Clark, Variability of annual rainfall in India, Geogr. Rev., 

 vol. 21, pp. 675-676, 193 1. 



