New YorK AGRICULTURAL EXPERIMENT STATION. 369 
with the open anthers of the former. The pollen-bearing cluster 
was also shaken against the castrated blossoms; finally, after 
being cross-pollinated thus, the cluster was usually covered 
with the bag which had contained the pollen-bearing cluster. 
After being closed with a wired label this bag was then shaken 
so that loose pollen, if it should contain any, might perchance 
alight upon some stigmatic surface. | : 
In these experiments the operation of cross-pollination was 
performed but once for each cluster. Whenever at the time of 
this operation a considerable percentage of the stigmas appeared 
not to be in good receptive condition note was made of this fact. 
This sometimes occurred when the pollen-bearing blossoms 
opened later than those which were to be cross-pollinated from 
them. When the conditions were reversed, and the blooming 
season of the pollen-bearing cluster was in advance of that of 
the variety to be cross-pollinated, the process of cross-pollination 
was, nevertheless, performed as above described. It is known 
that grape pollen may retain its vitality for days. 
Labeling.— On the label was written the particular number by 
which the cluster was designated in the experiment records, the 
name of the variety and the name of the pollen-bearing variety. 
The name of the mother plant was always written first, followed 
by x and the name of the variety with which it was cross- 
pollinated. Thus, “9471 Concord x Lindley ” indicated a par- 
ticular cluster of Concord, which, after being castrated, was 
cross-pollinated with Lindley pollen. 
VARIETIES UNDER EXPERIMENT. 
Self-sterile pollen! was tried upon the five strongly self-fertile 
varieties—Concord, Delaware, Diamond, Niagara and Worden— 
and also upon Vergennes, which is often less strongly self- 
fertile.2 The list of varieties selected to furnish pollen for the 
tests is given below. ‘In previous tests these varieties have 

1Throughout this discussion ‘‘self-sterile pollen’’-denotes pollen produced by self-sterile 
varieties; ‘‘imperfectly self-fertile pollen” and ‘‘self-fertile pollen” have corresponding sig- 
nificance. 
2The standing of Vergennes, as to self-fertility, is given on pages 370 and 372. 
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