66 PHILOSOPHICAL NOTES ON BOTANICAL SUBJECTS. 



siiri'onndiiigs makes the change more or less permanent. So that 

 in one instance we have the immense leaf of the Victoria regia, 

 the Musa, &c., while in the other, by almost a total abortion of 

 the mesophyl, we have the leaves of fennel, asparagus, and similar 

 plants. In one instance we have a large corolla, in another it 

 disappears. So of every part, including the root, stem, leaves, 

 cotyledons, hairs, &c. One term — suppression — means disappear- 

 ance of a part ; the others mean greater or less diminution. As 

 Dr. Masters shows, a diminution in one direction is often 

 counterbalanced by an increase in some other direction, the energy 

 of the plant remaining presumedly the same. So that in Achillea 

 and Senecio we have hundreds of small capitula, while in the 

 mammoth sunflower we may have only one. 



Reversion is a form of indirect inheritance. It is only a 

 return of some modified organ to a simple form from which it 

 arose, or through which it jJassed, such as the return to parts of a 

 flower to the leaf form (phyllody) . Or it may mean re-inheritance 

 of some ancestral form now belonging to some other plant, and 

 which had been suppressed or atrophied for a long time. A study 

 of seaweeds will probably show many parts, from which those of 

 Phnenogams may have l^een directly inherited, or to which thev 

 may have reverted, after passing through various modifications. 



