112 ESOHSCHOLTZIA CALIFOKNICA. CHAP. IV 



eeeds were examined by Professor Asa Gray, and pronounced 

 to belong to E. calif arnica, with which they were identical in 

 general appearance. Two of these plants were covered by a 

 net, and were found not to be so completely self-sterile as in 

 Brazil. But I shall recur to this subject in another part 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 maxi- 

 mum 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 grand-parents 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 experi- 

 ment 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 afresh 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 se 1 f -fertilised generation 

 of the Brazilian stock. 



Eight flowers on )ne of the crossed plants of the last experi 



