of this work.  Here it will suffice to state that eight flowers on these two plants, fertilised with pollen from another plant under the net, produced eight fine capsules, each containing on an average about eighty seeds.  Eight flowers on these same plants, fertilised with their own pollen, produced seven capsules, which contained on an average only twelve seeds, with a maximum in one of sixteen seeds.  Therefore the cross-fertilised capsules, compared with the self-fertilised, yielded seeds in the ratio of about 100 to 15.  These plants of Brazilian parentage differed also in a marked manner from the English plants in producing extremely few spontaneously self-fertilised capsules under a net.

Crossed and self-fertilised seeds from the above plants, after germinating on bare sand, were planted in pairs on the opposite sides of five large pots.  The seedlings thus raised were the grandchildren of the plants which grew in Brazil; the parents having been grown in England.  As the grandparents in Brazil absolutely require cross-fertilisation in order to yield any seeds, I expected that self-fertilisation would have proved very injurious to these seedlings, and that the crossed ones would have been greatly superior in height and vigour to those raised from self-fertilised flowers.  But the result showed that my anticipation was erroneous; for as in the last experiment with plants of the English stock, so in the present one, the self-fertilised plants exceeded the crossed by a little in height.  It will be sufficient to state that the fourteen crossed plants averaged 44.64, and the fourteen self-fertilised 45.12 inches in height; or as 100 to 101.

The effects of A cross with A fresh stock.

I now tried a different experiment.  Eight flowers on the self-fertilised plants of the last experiment (i.e., grandchildren of the plants which grew in Brazil) were again fertilised with pollen from the same plant, and produced five capsules, containing on an average 27.4 seeds, with a maximum in one of forty-two seeds.  The seedlings raised from these seeds formed the second self-fertilised generation of the Brazilian stock.

Eight flowers on one of the crossed plants of the last experiment were crossed with pollen from another grandchild, and produced five capsules.  These contained on an average 31.6 seeds, with a maximum in one of forty-nine seeds.  The seedlings raised from these seeds may be called the intercrossed.

Lastly, eight other flowers on the crossed plants of the last experiment were fertilised with pollen from a plant of the English stock, growing in my garden, and which must have been exposed during many previous generations to very different conditions from those to which the Brazilian progenitors of the mother-plant had been subjected.  These eight flowers produced only four capsules, containing on an average 63.2 seeds, with a maximum in one of ninety.  The plants