Chap. X. PLANTS FEKTILE WITHOUT INSECT- AID. 365 



List of Plants, which when protected from Insects are 

 either quite Fertile, or yield more than half the Number 

 of Seeds produced by unprotected Plants. 



Passiflora gracilis (Passifloracese). Produces many fruits, but 

 these contain fewer seeds than fruits from intercrossed flowers. 



Brassica oleracea (Cruciferse). Produces many capsules, but 

 these generally not so rich in seed as those on uncovered 

 plants. 



Jiuphanus sativus (Cruciferse). Half of a large branching plant 

 was covered by a net, and was as thickly covered with 

 capsules as the other and unprotected half; but twenty of 

 the capsules on the latter contained on an average 3 - 5 

 seeds, whilst twenty of the protected capsules contained only 

 1 85 seeds, that is, only a little more than half the number. 

 This plant might perhaps have been more properly included 

 in the former list. 



lbcris umhellata (Cruciferse). Highly fertile. 



J. amara. Highly fertile. 



Reseda odorata and lutea (Resedaceso). Certain individuals com- 

 pletely self-fertile. 



Euryaleferox (Nymphseacese). Professor Caspary informs me that 

 this plant is highly self-fertile when insects are excluded . He 

 remarks in the paper before referred to, that his plants (as 

 well as those of the Victoria regia) produce only one flower 

 at a time ; and that as this species is an aunual, and was 

 introduced in 1809, it must have been self-fertilised for the 

 last fifty-six generations ; but Dr. Hooker assures me that to 

 his knowledge it has been repeatedly introduced, and that at 

 Kew the same plant both of the Euryale and of the Victoria 

 produce several flowers at the same time. 



Nymphoea (Nymphseacese). Some species, as I am informed by 

 Professor Caspary, are quite self-fertile when insects aro 

 excluded. 



Adonis aestivalis (Ranunculacese). Produces, according to Pro- 

 fessor H. Hoffmann (' Speciesfrage,' p. 11), plenty of seeds 

 when protected from insects. 



Ranunculus acris (Ranunculacese). Produces plenty of seeds 

 under a net. 



Pjpaver somniferum. (Papaveracese). Thirty capsules from un- 

 covered plants yielded 15 ' 6 grains weight of seed, and thirty 

 capsules from covered-up plants, growing in the same bed, 



