354 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
degree of colouring or time of ripening of the fruit, but that cross- 
polHnation tends to raise the percentage of fruit setting even in self- 
fertile varieties the figures in the second table suggest. These figures 
go to show that interplanting varieties for cross -pollination, in the 
plantation or garden, should be the rule whether the varieties grown 
Self-Sterile — 
Coe's Golden Drop . 
221 flowers, selfed 
Decaisne .... 
2'7Q 
Q 
Grand Duke . . • . 
J^D »• )» 
Jefferson .... 
187 
'■^Z It It 
ICirke's Blue .... 
12^ 
^ J 11 II 
Late Orange .... 
216 „ 
1, 0 
Late Transparent Gage . 
138 .. 
Pond's Seedling 
Comte d'Althan's Gage . 
162 „ 
349 
0 „ 
Transparent Gage . 
403 
0 ,, 
Washington . . . . 
105 
„ 0 „ 
Self- Fertile — 
Denniston's Superb. 
300 
102 
Monarch .... 
59 
14 
The Czar .... 
284 
62 „ 
Partly Self-Fertile — 
Early Rivers .... 
337 
.1 25 „ 
President .... 
489 It 
3 
Prince Engelbert 
81 
6 
Stint 
273 
4 
be self -fertile or self -sterile, where the maximum amount of fruit 
" setting " is desired. 
The percentages of fruit setting when crossed represent the result 
Percentage of Fruit Setting, Crossed and Selfed. 
Denniston's Superb 
300 
flowers. 
selfed 
set 
102 fruits, or 
34 
per 
cent. 
128 
crossed 
51 It 
39-8 
Monarch 
59 
flowers. 
selfed 
set 
14 fruits, or 
23*7 
per 
cent. 
199 
crossed 
50 » 
25.1 
The Czar 
284 
flowers. 
selfed 
set 
62 fruits, or 
21-8 
per 
cent. 
123 
crossed 
36 „ 
29*2 
Early Rivers . 
337 
flowers. 
selfed 
set 
25 fruits, or 
7-4 
per 
cent. 
207 
crossed 
43 
20-7 
President 
489 
flowers. 
selfed 
set 
3 fruits, or 
0-6 
per 
cent. 
223 
crossed 
57 It t. 
25-5 
Stint 
273 
flowers, 
selfed 
set 
4 fruits, or 
1.4 
per 
cent. 
231 
crossed 
28 „ „ 
I2'I 
Prince Engelbert 
81 
flowerr. 
selfed 
set 
6 fruits, or 
7-4 
per 
cent. 
74 
crossed 
43 
58-1 
of crossing the varieties with the majority of the other seventeen 
varieties in the experiment. 
That pollen from one variety will fertilize a higher percentage of 
flowers on a certain other variety than will the pollen from another 
seems possible, but sufficient data has not yet been collected on this 
point. 
The evidence obtained so far goes to show that, with a few ex- 
ceptions, any one variety will successfully cross-pollinate any other 
variety, providing that they flower at much about the same time. 
The exceptions to this are the Coe varieties of plum and Jefferson — 
