14 
1ST. C. Agricultural Experiment Station 
of Rubus trivialis, and those varieties in which trivialis blood predomi¬ 
nates, are self-sterile, while those varieties that come from Rubus villosus 
generally are self-fertile. Of this last named species, two varieties, 
Premo and Rathbun, prove to be exceptions under our observation. 
Premo exhibits absolute self-sterility, while Rathbun (a hybrid) is only 
partially self-fertile. 
However, with only two varieties of Rubus villosus proving to be 
positively self-fertile, and one decidedly self-sterile, it was deemed ex¬ 
pedient to test the species at large, that is, the wild species, before 
making any generalizations. 
Rubus villosus is indigenous to our soil and climate, and the vines are 
to be found growing profusely and abundantly in and about our fields 
and woods. Accordingly, in the spring of 1915 twenty individual wild 
vines were marked, and on April 20th five clusters of flower buds on 
each of the vines were covered with cloth and paper bags. 
If the species be self-sterile, we would find no fruits in the bags during 
the fruiting season; if the species be self-fertile, then we should expect 
to see a crop of berries in each of the undisturbed bags; if the species 
be composed of both self-fertile and self-sterile vines, then we should 
expect to get varying results. The following table shows the results of 
this test : 
Table No. 4 
Number of Vine 
Species 
Number 
of Bags 
Recovered 
Number 
of 
Fruits 
Number 
Without 
Fruits 
No. 1_ 
Villosus 
4 
4 
n 
No. 2_ . 
Villosus 
4 
2 
2 
No. 3_ . 
Villosus 
4 
3 
1 
No. 4 ... .. _ 
Villosus 
1 
0 
1 
No. 5_ 
Villosus 
5 
0 
K 
No. 6_ . _ . 
Villosus- 
5 
4 
1 
No. 7_ 
Villosus 
3 
2 
1 
No. 8 -. . 
Villosus 
5 
4 
1 
No. 9._ 
Villosus 
4 
2 
2 
No. 10_ 
Villosus 
9 
9 
o 
No. 11_. 
Villosus 
10 
10 
o 
No. 12 . 
Villosus 
9 
"9 
o 
No. 13_ . 
Villosus 
5 
5 
o 
No. 14_ 
Villosus 
6 
1 
No. 15_ 
Villosus 
11 
11 
o 
No. 16_ 
Villosus 
14 
3 
11 
No. 17_ 
Villosus. 
4 
4 
o 
No. 18 ... . 
Villosus 
5 
4 
1 
No. 19.. 
Villosus 
5 
5 
o 
No. 20_ 
Villosus. . _ _ 
5 
5 
0 
From the tabulated results, the fact stands out very clearly that the 
species Rubus villosus at large is quite self-fertile. From this it is 
evident that the case of the variety Premo is simply an exception to the 
general rule, and requires special investigation. 
