UNCLE IN ENGLAND. 301 



" Another opinion," added my uncle, "is, 

 that the fibres of the leaf-stalk are not a simple 

 continuation of those of the twig or branch, but 

 that they both terminate at that point from which 

 the leaf falls ; being only connected by a kind 

 of adhesive substance, which dries up when the 

 sap ceases to rise. This point of separation you 

 may easily perceive," said he, " like a cicatrice, in 

 the form of a ring ; and the same appearance of 

 a natural separation is to be seen in the pedun- 

 cles of flowers, which seem also to be attached 

 by a sort of vegetable solder to the stem." 



" But, uncle, why then do not leaves fall much 

 sooner, if they are so slightly attached to the 

 stem ?" 



" Because this adhesive substance is a strong 

 cement, as long as it is supplied by the vegetable 

 juices. If you attempt to remove the stalk 

 elsewhere than at that point where it is united, 

 the fibres are lacerated; and this proves that 

 the separation had been prepared for at that one 

 point, by some peculiar organization which acts 

 independently of frost or rain, or other external 

 causes." 



My uncle then shewed me the ring which 

 marks the point of separation. It is most easily 

 seen in autumn, he says ; it is double in the 

 orange, and in the berberry he shewed me that 

 it is above the point of contact between the leaf 

 and branch, so that after the fall of the leaf, the 



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