The Bulletin 
13 
ever set on eacli of tliese clusters. The largest bunch of berries that 
was ever observed on this vine consisted of only ten berries, while the 
largest hunch of rotnndifolia grapes ever observed by the writer was 
composed of thirty-five berries." The number of berries per cluster 
varies with the general care of the vine. 
The number of fruit clusters on the vine depends on many factors, 
among which the actual number of flower clusters produced, the degree 
of development of the pistils, and the amount of shedding that takes 
place soon after the flowers are fertilized are important items and de¬ 
mand consideration. 
Self-fertility of Hope Vine .—In order to determine the exact status of 
the Hope vine in regard to the question of self-fertility, the following 
work was carried out: 
In 1910, as soon as the vine was discovered, although this happened 
late in the season, two flower clusters which were still in bud were 
observed and immediately bagged. These bags were left undisturbed 
until all of the buds had bloomed, and later, upon examination of the 
contents of the bags, no fruit was found to have developed. The other 
parts of the vine bore. an average crop of fruit which was produced 
from the normal flowers of the season. 
In 1911 the experiment was repeated and, because of a greater supply 
of flower clusters, thirty-five branches were bagged and left to their 
fate. Hot one of these thirty-five branches produced as much as a berry, 
but neither did the other parts of the vine bear any fruit. 
In 1912 ten more branches, with two or more clusters to the branch, 
were covered. Although the vine bloomed profusely, no fruit was pro¬ 
duced that year either in the bags or on the exposed branches of the 
vine. 
In order to determine whether this vine failed to set fruit because of 
an existing uncongeniality between the pistils and the pollen of the 
same vine, or because of the lack of viable pollen, nineteen branches 
were bagged in 1911 and cross-pollinated with fresh pollen from a light- 
colored staminate vine. This pollen, although from a staminate vine, 
had no more effect on the setting of berries than did the pollen from the 
same vine, for no fruit was produced in the bags. The pistils, therefore, 
seemed to be faulty and incompetent to set fruit at times, regardless of 
the kind and source of pollen. 
In 1913 only two berries were observed on the whole vine, and in 1914 
only a handful, less than a dozen berries, constituted the total crop of 
fruit. 
These negative results pointed very strongly toward sterility of the 
vine. It seems that for some unknown reason the vine appeared to 
have reverted all at once from a fruit-bearing vine to one that functions 
essentially as a staminate vine. 
*In 1914 a Luola vine pi’oduced an exceedingly heavy crop of fruit, and among the many 
large clusters one was found composed of 35 berries. 
