DECEMBER. 359 



C. Why does a plant die if its bark be cut round ? 



F. Because the vegetative life resides in the liber, and 

 if this be divided, as in girdled trees, so that the upper part 

 has no contact with the lower, no more buds or leaves can 

 be put forth, these being produced from the inner surface of 

 the liber. But if it be divided in part, that side of the tree 

 whose connexion is unbroken will continue to nourish, while 

 the portion immediately above the separated bark, withers 

 and dies, as may be seen in a hundred instances in our 

 forests. 



C. I have often wondered at the huge globular excres- 

 cences that stand out from the trunks of some trees, such as 

 the maple, but more especially the birch ; sometimes as large 

 as a hogshead. Do you know the cause of them ? 



F. I do not, accurately; on being cut, they present 

 the regular structure of wood, surrounded by bark, but re- 

 markably twisted and gnarled in the grain : in the centre is 

 always some cavity or defect. I suspect they are either a 

 diseased growth of the tree, like wens in animals, or the 

 accumulated layers of ages around the base of some broken 

 limb. 



But we have finished a year ; the seasons have completed 

 their annual course, since we commenced our wild wood- 

 land rambles ; many subjects of interest have fallen beneath 

 our observation ; many phenomena, more or less obvious, 

 have occurred to our notice, calculated, I trust, to make us 

 wiser and better. If they have tended to enlarge our inform- 

 ation, to increase our cheerfulness, to calm and elevate our 

 minds, to enforce a merciful consideration towards inferior 

 animals, to open before us a wider display of the power, wis- 

 dom, providence, and benevolence of Him who is essential 

 Love, why, we have not wasted our time. But we have 

 seen but a small portion of the mysteries of nature ; inex- 

 haustible stores yet remain to be unlocked ; interesting and 



