368 
PEOFESSOR K. PEARSON ANE* OTHERS ON 
of fully ripened seeds—and this only when the pods were not infested with grubs. EVe 
did the best we could to count the aborted seeds, but we cannot be certain that all 
those counted as aborted were non-fertilised, or that we succeeded in counting aU 
those which had shrunk to microscopic j^roportions. The number of ovules is simply 
the sum of the ripe and the aborted seeds counted in each pod, and this again must be 
somewhat doubtful. The reader will bear in mind that we proceeded with care, but 
that we think it right, if anything, to rather over- than under-emjDhasise possible 
sources of error. Yet allowing for such sources of error we cannot, on examining the 
results given in Table LI., allow that Brooin is in the least rej^resentative of the 
degree of homotyposis to be found in the pods of leguminous plants. Whether we 
consider the ovules, the ripe, or the aborted seeds, our results are sensibly below that 
for broom, and the mean of the whole sixteen series gives us a value about one-half 
that of the homotypic correlation based ujDon characters not depending on fertilisation. 
If we deal with averages, it v^ould certainly seem that in the results flowing from 
fertilisation, we have reduced the intensity of the individuality to about half its 
previous value. 
To this extent only does the individual constitution appear influential in the 
number of seeds in the pod, the remainder of the homotypic intensity seems to have 
disappeared under random influences having nothing to do with the individuality of 
the plant. This is perhaps what we might expect in the case of ripe seeds in cross- 
fertilised plants, where the fertilisation may depend on the chance or not of insect 
visitation and tlie effectiveness or not of the pollen brought on such occasions. We 
should have to assert that the bird’s-foot trefoil and the everlasting pea, whose 
average for homotypic correlation in the case of rijje seeds is about '21 to '22, lose 
half the intensity of their individuality through the random nature of the chances of 
the cross-fertilisation. But although this might be fairly satisfactory for these cases, 
what are we to say for the species which are self-fertilised absolutely or self-fertilised 
in default of cross-fertilisation ? We might have exjoected a high degree of homotyposis 
in the field bean or the tare vetch, where failing cross-fertilisation we are told there 
will be self-fertilisation. We find on the contrary, however, in these results some of 
the lowest homotypic correlations of the whole series. The sweet pea also in its two 
series presents some very remarkable results. If the sweet pea be entirely self- 
fertilised then we should expect the homotyposis of both ovules and ripe seeds to be 
fully up to the average. In neither case is such a result reached, although in one 
series we have a value for the ovules higher than that obtained for anything 
except the broom. The noteworthy fact, however, is that the results for the two 
series of sweet peas differ so widely in character ! In the first series it is the 
al)ortion which is most individual in character; in the second series it is the ovules. 
In the first series the ripe seeds have far less iudividuality than the aborted seeds, 
in fact, the smallest homotyposis I have yet observed ; in the second series the ripe 
seeds have a value rising to '2, which is higher than that of the aborted seeds. Ash 
