528 Pieters — Influence of Fruit-bearing on 
fruit-bearing than in the vegetative shoot, and relatively 
smaller in the swollen portion than elsewhere. 
Table 9, — Average proportion of tissues in — 
Per cent. 
Five vegetative shoots . 
35-22 
33-98 
28.78 
Five fruit-bearing shoots 
3Q-9 1 
39-69 
I9-25 
- 4.31 
+ 5-7 1 
-9*53 
In the small swollen area at the base of the fruit-stub the 
zone of wood is thicker than it is a little lower in the same 
shoot, but the walls of the wood-cells are thin and mostly 
unlignified. 
Table 10. — Actual average measurements of the shoots and measurements 
through the swollen part. 
Cortex. 
Wood. 
Pith. 
Total. 
Five vegetative shoots 
65 
63 
53 
181 
Five fruit-bearing shoots . 
59 
77 
55 
191 
Five fruit - bearing shoots 
through swollen part 
78 
87 
53 
218 
Summary. 
The study of these four species seems to warrant the 
following conclusions, in answer to the questions proposed 
at the beginning of this paper : — 
1. The one-year-old fruit-bearing shoots of the Apple and 
the Pear have less wood in proportion to their diameter than 
does the vegetative shoot of the same age. This is due, in 
the Apple, largely to an increase in the cortex, and in the Pear 
solely to a great increase in the cortex and the pith, of the 
fruit-bearing shoot. It does not, however, appear from the 
structure of the shoots that the fruit-bearing shoot is weaker 
than the vegetative. The former is well supplied with 
supplementary mechanical tissue, which is distributed at 
those points where it is most needed, and thus gives it an 
increase of strength for the fruit-bearing year which fully 
makes up for the difference in xylem-development. 
