THE THREE FORMS OF LYTHRUM SALICARIA. 181 
Table I.—Lona-stTyLED Form (continued). 
III. IV. 
14 flowers fertilized by the short | 12 flowers fertilized by the shorter 
stamens of the mid-styled. stamens of the short-styled. 
3 0 20 0 
0 0 0 
0 0 0 0 
0 0 0 0 
0 0 -— 0 
— 0 0 0 
0 0 
0 Too sterile for any average. 
Too sterile for any average. 
V. VI. 
15 flowers fertilized by own longer | 15 flowers fertilized by own shorter 
stamens, stamens. 
2 — 4 — 
10 0 8 0 
23 0 4 0 
0 0 0 0 
0 0 0 0 
0 0 0 0 
0 0 0 0 
0 0 0 
Too sterile for any average. Too sterile for any average. 
I fertilized a considerable number of flowers with pollen, taken by a 
camel’s-hair brush, from both the long and short stamens of their own (long- 
styled) form; but I did not examine with a lens (as I did in the cases in 
the Tables) whether sufficient pollen had been placed on the stigma: only 
5 capsules were produced, and these yielded on an average 14°5 seed. In 
1863 I tried a much better experiment: a long-styled plant was grown 
by itself, miles away from any other plant, so that its stigmas could have 
received only the two kinds of pollen proper to this form. The flowers 
were incessantly visited by bees, so that the stigmas must have received 
on the most favourable days, and at the most favourable hours, successive 
applications of pollen: all who have crossed plants know that this highly 
favours fertilization. This plant produced an abundant crop of capsules ; 
I took by chance 20, and these (excluding one poor one) contained seed as 
below :— 20 20 35 21 19 
26 24 12 23 10 
7 30 27 29 13 
20 12 29 19 35 
This gives an average of 21:5 seed per capsule; and as we know that this 
form, when standing near plants of the other two forms and fertilized by 
insects, produces an average of 931 seed per capsule, we see that the 
long-styled form fertilized by its own two pollens yields only between 
one-fourth and one-fifth of the full number of seed. I have spoken as if 
this plant had received both its own kinds of pollen, and this is, of course, 
possible; but, from the enclosed position of the shorter stamens, it is 
much more probable that the stigma received almost exclusively the pollen 
from its own longer stamens. 
