THE THREE FORMS OF LYTHRUM SALICARIA, 179 
repeated each of the eighteen unions a score of times; but the 
labour would have been too great; as it was, I made 223 artificial 
unions; 4. e., I fertilized, on an average, above a dozen flowers in 
the eighteen different methods. Each flower was castrated ; the 
adjoining buds had to be removed, that the marking-thread, wool, 
&e. might be safely secured; and after each fertilization the 
stigma had to be examined with a lens to see that there was suf- 
ficient pollen. Plants of all three forms were protected during 
two years by large nets on a framework ; two plants were used 
during one or both years, in order to avoid any individual pecu- 
liarity in any one plant. As soon as the flowers withered, the 
nets were removed; and-in the autumn the capsules were daily 
inspected ; when the seeds were ripe they were counted under 
the microscope. I have given these details that confidence may 
be placed in the following Tables, and as some excuse for two 
blunders which, I believe, I made. These blunders are referred 
to, with their probable causes, in two notes to the Tables; the 
erroneous numbers, however, are entered in the Tables, that it 
may not be supposed that I have in any one instance tampered 
with the results. 
A few words explanatory of the three Tables must be given. 
Each is devoted to one form, and is divided into six compartments. 
The two upper ones in each table give the product of good seed 
from the application of pollen from the two sets of stamens which 
correspond in length with the pistil of that form. The two next 
lower compartments show the result of pollen from the other two 
sets of stamens, which do not correspond in length with the pistil, 
and which are borne by the same two forms. The two lowest 
compartments show the result of the application of each form’s 
own two kinds of pollen. The term “own pollen,” used here and 
in the Tables, does not mean pollen from the flower to be fertilized 
— for this was never used—but from another flower on the same 
plant, or more commonly from a distinct plant of the same form. 
In the result given, “0” generally means that no capsule was 
produced, or that the capsule contained no good seed. In some 
part of each row of figures in each compartment, a short hori- 
zontal line may be seen ; the unions above this line were made in 
1862, and below it in 1863. It is of importance to observe this, 
as it shows that the same general result ensued in two successive 
years ; but more especially because 1863 was a very hot and dry 
season, and the plants had occasionally to be watered. This did 
not prevent the full complement of seed being produced from 
