174 PHILOSOPHICAL NOTES ON 



only when plants had become parasites that they again dispensed 

 with roots. 



That the frond or leaf portion of the plant was anterior in 

 evolution to the root portion seems more than probable, but I do 

 not think there is any grounds whatever for considering the root 

 and branch as essentially different. 



In a large number of plants buds are given ofi by the roots, 

 and in many others roots are given off by the stem and branches. 

 All this shows that, morphologically, there is no distinction between 

 the root and any other part of the plant. 



In Vancla and other orchids there are aerial roots at the base 

 of each leaf, but as these are in an air medium they retain the 

 general character of the terete leaves of some orchids. These 

 orchid adventitious roots often serve as organs of attachment, like 

 the fingered disks of seaweeds. Vanda has a tall stem weighted 

 with many leaves. In a storm it would be blown down and 

 destroyed. Natural selection has developed in it long aerial 

 roots, you may call them tendrils — which grow in search of some- 

 thing to adhere to, as props to the stem. As the primitive roots 

 of seaweeds originally served only as a means of attachment, so 

 these orchid roots serve a similar purpose now. 



Why have many plants lost the power of giving off' root-buds 

 from the stem unless artificially coaxed to do so by the horti- 

 culturist ? We do not know. We might ask similar questions 

 about other parts of plants. For instance, why has the Nasturtium 

 lost the power of producing stipules, when its first leaves have 

 them } The loss may have occurred either through their not 

 needing them, by atrophy, or through congenital variation. 



Certain plants either need shoots on their roots, for battle 

 purposes, or they do not need them, having other weapons. Then 

 the energy of the plant, being diverted into other weapons, the 

 power of root-budding atrophies. If the total energy be great, the 

 habit of root-budding may be maintained, and then the struggle 

 for life has a greater chance of success, for, however, much the 

 above-ground portion may be destroyed by animals, storms, fire, 

 or other causes, the underground portion will reproduce the very 

 same plant, with whatever accumulated advantages for struggle it 

 may have already j^ossessed, through inheritance. 



By root-budding the plant has not only an alternative mode of 

 producing seed, in case of total destruction of the branches, but 



