112 CHRISTISON—OBSERVATIONS ON 
C. General Conclusions from the Monthly History of 
the Species. 
In considering some of the conclusions that may be drawn 
from the history of the species, it is necessary to adopt three 
categories according to the degree of reliability in the results 
obtained in the different species. The first includes the species 
of the period 1891-94 (in which only one example of each was 
observed) that yielded results in conformity with those obtained 
from one or more trees of their own species under observation 
in 1887-91. The second comprises the species in which the 
results for the two periods are at variance, or are otherwise 
invalidated. The third contains the species of which only one 
tree has been under observation. 
The chief points to which attention will be directed are the 
comparative tendency in the different species to early or late 
increase in girth during the growing season, and the compara- 
tively wide or limited distribution of the girth-increase over the 
growing season in the different species. 
I. Species in which the resnilts for 1892-95 and for 1887-91 
are in substantial agreement. 
In this category the results are naturally the most reliable, 
and may be held to establish fairly well the characteristics of the 
species included, in regard to the points under consideration. 
(a.) The comparative tendencies of the species towards 
early or late increase in girth during the season of growth 
are shown in the Table which gives the percentage of girth- 
increase due to each month in the trees of 1887-91 and of | 
1892-95 combined, the arrangement being in the order of 
greatest tendency to increase in the latter half of the season. 
[ TABLE. 
