340 SELF-STERILE PLANTS. Chap. IX. 



The other plant was partially self-sterile, producing 

 very few capsules, many of which were of small 

 size. When, however, this plant had grown tall, 

 the uppermost branches became pressed against the 

 net and grew crooked, and in this position the bees 

 were able to suck the flowers through the meshes, and 

 brought pollen to them from the neighbouring plants. 

 These branches then became loaded with capsules; 

 the other and lower branches remaining almost bare. 

 The sexual constitution of this species is therefore 

 similar to that of Reseda odorata. 



Concluding Remarks on self-sterile Plants. 



In order to favour as far as possible the self-fer- 

 tilisation of some of the foregoing plants, all the 

 flowers on Reseda odorata and some of those on the 

 Abutilon were fertilised with pollen from other 

 flowers on the same plant, instead of with their own 

 pollen, and in the case of the Senecio with pollen from 

 other flowers on the same corymb ; but this made no 

 difference in the result. Fritz Muller tried both kinds 

 of self-fertilisation in the case of Bignonia, Tabernae- 

 montana and Abutilon, likewise with no difference in 

 the result. With Eschscholtzia, however, he found 

 that pollen from other flowers on the same plant 

 was a little more effective than pollen from the 

 same flower. So did Hildebrand* in Germany; as 

 thirteen out of fourteen flowers of Eschscholtzia thus 

 fertilised set capsules, these containing on an average 

 9 5 seeds ; whereas only fourteen flowers out of twenty- 

 one fertilised with their own pollen set capsules, 

 these containing on an average 9 seeds. Hildebrand 



* Pringsbeim's Jabrbucb. fur wiss. Botanik,' vii. p. 467 



