discovered in Cralgkith Quarry. 149 



On the edges of A was not more than 7 inches. From the 

 diameter of the highest part mentioned, it appears quite evi- 

 dent that many feet of the top part of the stem must have been 

 taken away unobserved, ere it attracted the notice of the public, 

 leaving fair ground to conclude, that, when it waved in the 

 winds which whistled through its spreading branches, for aught 

 we can say, a million years ago, its magnificent trunk stood 

 tall and stately full 60 feet in height. Judging from the un- 

 worked rock near where the stem lies, the superincumbent 

 mass must have been above 100 feet. The stem tapers gradu- 

 ally, and is marked at irregular intervals with a kind of transverse 

 rugas, or irregular prominences. The bark has been converted 

 into coal, and presents indistinct longitudinal markings, with 

 very small transverse ridges. At some of the prominences, the 

 ruga? are contorted like the coming off of branches of various 

 trees. That the forms of fossil trees are frequently much altered 

 prior to their consolidation, or during the process of petrifac- 

 tion, there can be no doubt. The shapes themselves, and the 

 circumstances in which they are discovered, often sufficiently bear 

 evidence to the fact, that pressure and other agents have been at 

 work. But recourse has often been had to this mode of explana- 

 tion in cases where it could not apply, and where one much more 

 easy was at hand. It is by no means uncommon to find amongst 

 recent trees, forms similar to those of fossil plants, which have 

 been ascribed to pressure and other external causes. Every one 

 who has had the opportunity, and has availed himself of the oc- 

 casion, must have observed this. The flattening, therefore, of 

 this fossil tree, is only similar to what exists in living nature, al- 

 though I am unwilling to believe that to be the case in this 

 splendid instance of early vegetation. The usual way of account- 

 ing for such flattenings is by pressure, although in the present 

 case, where the tree is not parallel to the strata, it is rather diffi- 

 cult to suppose its form to be owing to that cause. The pressure 



VOL. XII. PART I. U 



