520 Pieters.— Influence of Fruit-bearing on 
The first table shows the percentage of each tissue and the 
amount of difference in the development of the tissues in the 
shoots. In the second table are given the actual measure- 
ments of the tissue-zones. These furnished the data from 
which the percentages in the first table were derived. 
Table i. — Average percentage of tissue in one-year-old shoots of Rhode Island 
Greening Apple. 
Cortex. 
Wood. 
Pith. 
Per cent. 
Per cent. 
Per cent. 
Twelve vegetative shoots 
40-74 
21-48 
37-77 
Twelve fruit-bearing shoots . 
47-97 
19.36 
32-66 
+ 7.23 
— 2-12 
— 5 - 11 
The percentages given in the above table were computed 
from the figures in the following table : — 
Table 2. — Average absolute amotint of tissue in 1 — 
Cortex. 
Wood. 
Pith. 
Total. 
Twelve vegetative shoots 
90-6 
47-77 
84 
222-37 
Twelve fruit-bearing shoots 
102-8 
4 i - 5 ° 
7 o 
214.30 
+ 12-2 
-6-27 
-14 
-8-07 
Both the above tables show a larger amount of cortex in 
the fruit-bearing than in the vegetative shoot, while the wood 
and pith are more abundant in the latter. The difference in 
the amount of wood is small, reaching little more than 2 per 
cent., or only 94-05 micromillimetres in absolute measure. 
At the base the fruit-bearing shoot is smaller than the 
vegetative shoot. The characteristic swelling begins a little 
above the basal zones of scars. Above this point both the 
cortex and the wood increase in size, but the proportion of 
cortex increases most rapidly. 
To determine the relative thickness of the walls of the 
1 In terms of the spaces of the eye-piece micrometer. Each space equals 
1 5 micromillimetres. 
