242 GENERATION. 



matter on the end of an old branch, or that of new branches, there is 

 every year a layer of new wood laid upon the outside of the former 

 wood. This new layer, when forming, has the power of producing a 

 new part, and never afterwards. Cut off a branch, and you will find 

 that the new layer forming round the cut surface receives a stimulus 

 arising from the want of power to continue this part of the tree, 

 which stimulus produces a new branch or branches. But an originally 

 formed part never produces a monster or a new branch ; we never see 

 a monster or branch arise from the cut surface of an already formed 

 part of a vegetable. In a vegetable it is always in the production of a 

 new part, not in the growth of the old, that monsters rise up. If a 

 vegetable meets with an accident which interferes with the natural 

 growth, it then forms itself into another growth. If a natural branch 

 decays, or is destroyed, two or three shall arise in its place, all of 

 which are so many monsters ; and we may observe that they are similar 

 to the other parts of the tree from which they arise. If it is in the 

 root, a new root is formed ; the same of a branch. They are only 

 supernumerary parts ; and this arises from a vegetable consisting only 

 of two parts, the old and the new ; the one only a repetition of the 

 other ; which is not the case with many animals that admit of mon- 

 strosity. 



Many plants have a deficiency in their shoots. Hence a vegetable 

 can be made to grow of a very different shape from that which it would 

 have done naturally. A tall thin tree can be made to grow short, thick, 

 and bushy, and vice versa ; but, still each new supernumerary part 

 attains the character of the tree and produces the same seed. 



The great principle of monstrosity in a vegetable relates to the con- 

 stant property of forming new and similar parts, and to a stop being 

 put to, or a violence committed to, the natural growth of one of these 

 parts. 



Monsters in Animals. 



As there are monsters in animals, let us see how far they are or are 

 not reducible to the same principle as in minerals and vegetables. The 

 first formation and growth of these are not similar to each other ; how- 

 ever, the vegetable and animal have the closest analogy 1 . 



I have observed that a crystal forms and increases according to the 

 nature of the parts of which it is to be composed ; and this is common 

 to all kinds of earth : but I observed that a vegetable is formed of a 

 peculiar modification of matter, and that common matter must be first 

 modified by the actions of the vegetable itself ; and this matter is dis- 



1 [Hence the present received division of Nature into the Organic and Inorganic 

 Kingdoms.] 



