BOTANICAL SUBJECTS. 75 



However distorted a form the fusion of composite heads may at 

 first produce, its seedlings will tend gradually, and generation 

 after generation, to reproduce the circular form. 



Similarly, two fused oranges or lemons will eventually produce, 

 through the seed, a perfectly globular though larger form. 



Then we may look upon it as pretty well proved that 

 monstrous forms, which occasionally occur in plants under 

 cultivation, and are thrown away as unholy, may, in a state of 

 nature, have laid the foundation of new varieties and species on 

 monstrous lines ! 



There is no such thing in nature as an abnormality. The 

 apparent abnormality is as normal a phenomenon, as what we call 

 a normality. "We may as well call a planet abnormal, because it 

 has one satellite, or because it has none, or more than one ! 



The question remains, why are] all ^vild Composites circular in 

 form, whether the flower heads are small or large ? 



First. — We do not know that oval forms do not now and then 

 occur in the wild state. They may, if ever met with, have been 

 overlooked as monstrous. Second. — Fusion under cultivation 

 occurs associated with luxuriance, and luxuriance in a wild state 

 can rarely occur where seeds are scattered without number, and 

 the resulting seedlings have to struggle for their life with each 

 other and with other plants. Consequently they are starved, and 

 that luxuriance which tends to fusion is generally absent. 



If by chance a seedling were to fall on very favourable soil, and 

 be surrounded by very favourable conditions, fusion would not 

 occur of a sudden, because heredity would oppose it. If fusion 

 did, by some chance, occur under such circumstances, every trace of 

 it might be extinguished, in a certain number of generations, by 

 ihe polar force, to which I have just alluded, and which is always 

 acting, if unopposed by some stronger force, such as that of 

 heredity. 



Whatever the reason may be, I think that this phenomenon of 

 fusion may help us to conceive how composites with small 

 capitula can evolve others with larger and larger capitula ; and in 

 it we have evidence that sexual conjugation is not the only source 

 of variation. 



The fusion of stems in the cockscomb is verv instructive. It 

 shows that stems originally terete and slender can be kneaded into 

 a flat blade, without any trace of its component stems. The 



