1847.] South Carolina Agricultural Society. 37 



in which animal remains exist, which are rather peculiar to a 

 climate more severe than the present in this latitude, may be 

 accounted for on the ground that a cold current from the north 

 from the* "direction of the St. Lawrence gulf, flowed at this 

 period through these valleys into the bay of New York. But such 

 a current, admitting its existence, would not materially alter the 

 climate of the whole country. The effect would be quite local, 

 and would be sufficient only to bring about a few slight changes 

 in the distribution of the molusca, and perhaps to a certain ex- 

 tent of a few animals of a higher order. 



We repeat then in conclusion, that it is unnecessary in account- 

 ing for the extinction of those peculiar races, to maintain that 

 a change in climate destroyed them, or that they perished during 

 some violent catastrophe. 



RENEWAL OF BARK. 



The destruction of the bark of trees does not necessarily result 

 in their death. Mice and other gnawing animals devour the bark 

 of fruit trees; but if the wood is not also badly injured the tree 

 need not be considered as lost. The wood, if properly covered 

 with a composition of wax, will give an opportunity for the in- 

 jury to be healed, either by a renewal of bark over the whole 

 surface, or else by a lateral closure by the extension of new wood 

 and bark. 



In order that the bark should be replaced at once, it is neces- 

 sary that the outer layer or the newly ibrmed wood should be un- 

 injured. A proof that the entire bark of the body of a tree may 

 be renewed or secreted, is furnished in facts and observations 

 which we have recently made upon the white or paper birch, 

 [Betida pnpulifera). It is not uncommon for this birch to be 

 stripped of its w^hite and singularly laminated cuticle for five or 

 six feet, along the lower part of the trunk. The consequence is, 

 the whole of the tree's bark beneath is killed; when it cracks 

 and splits off" after a time. The tree itself, however, appears to 

 suffer but little; for soon new bark is formed beneath the old. 

 Even the restorative energies of the tree are sufficient, after a 

 year or two, to form anew the white and peculiar cuticle; and we 

 frequently have seen the old and dead bark remaining upon the 

 outside, and the white cuticle beneath it presenting a curious 

 instance of the presence of bark with the cuticle beneath the tree's 

 bark of an anterior date. 



