342 EFFECTS OF THE GRAFTING AND BUDDING OF TREES, 



that would convince the most unbelieving, and prove, that 

 the process of the formation of the wood proceeds in this 

 manner. When the sup begins to rise, it detaches the rind, 

 the baric, and inner bark, in one close layer, from the 

 wood; and they, being disposed to grow faster than tlte 

 inner part of the stem, increase as much as the fastening 

 of the flower buds to the wood will permit. The sap then, 

 forms the new wood in the intervening space, and a band 

 is completed each year. 

 Lusus nature. I found some time ago a lusns naturae, which teaches 

 more than all I can say on the subject; and I have given as 

 exact a drawing of it as I could make. See pi. x. jig. 1. 

 On looking at some plants, I observed a Portugal laurel ap- 

 peared in a very strange state ; and on examining it, I per- 

 ceived some accident had separated the rind, bark, and inner 

 bark, in two regular bands, from the stem of the tree. Still, 

 however, the ends were attached, but the loose part, from 

 being at liberty, had so wonderfully increased in length, 

 that it was more than double the measure of the piece of 

 stem it originally covered. It had broken the trilling hold 

 of the nourishing vessels, and that of the flower buds, 

 which, when I found it, were perfectly dead, but still it 

 had thrown out its leaves, and was forming fresh ones. On 

 dissecting the leaves, there appeared no nourishing vessels, 

 or their emptiness prevented their being distinguished ; and 

 the spiral wire was only to be found now and then, and in 

 a broken and dilapidated state. I deeply regretted the hav- 

 ing separated the branch from the stem, before I knew what 

 it was. Butit is still a very great curiosity, and explains well 

 the powers of the different parts. It plainly marks, that 

 therind, bark, and innerbark, are the formers of the leaves; 

 and that though they receivemost part of their nourishment 

 from the nourishing vessels which spring from the wood, 

 yet they can expand and form without them. They did not 

 indeed appear in perfect health, nor could it be expected, 

 as their whole nourishment came from the dew they re- 

 ceived, and the carbonic acid gas they inhaled. The inner 

 bark vessels were full of ( the blood of the plant, and did not 

 appear to evaporate in any manner, though one side was ex- 

 posed ; which shows how very complete must be the sepa- 

 ration between the blood of the plant and its sap. 



It 



