Rev. T. G. Bonney — LithodomouB Perforations. 317 



After this I searclied no more in Miller's Dale, but went on by the 

 Wye, until I came to the entrance of Tideswell Dale, up which I 

 turned. After walking about a third of a mile (some 300 yards 

 from the sharp turn where we lose sight of the entrance to the dale), 

 a bed of limestone rose from the roadside on the right bank, and 

 mounted gradually up the sloping side of the valley. Here, at- 

 tracted by the appearance of the rocks, I again began to search, and 

 found the burrows at intervals, commencing a few feet above the 

 road. Some 40 feet above the stream rose a small crag, about four 

 feet high, in the upper part of which they were very abundant ; from 

 this I detached a fine specimen, which I have placed in the Wood- 

 wardian Museum. 



I then walked on to the marble quarry mentioned by Mr. Brown 

 (G-EOL. Mag. Vol. VII., p. 585). Here I found burrows plentifully, in 

 reefs of limestone projecting from the hill-side right and left of the 

 quarry, and nearly on the horizon of the marble-bed. Again, I noticed 

 them on a crag just off the road on the left bank of the valley, and two 

 or three hundred yards out of Tideswell. Eeturning thence I fol- 

 lowed, for a short distance, the upper road on the right bank of the 

 valley ; and here, shortly before coming opposite to the quarry, I 

 saw that some projecting slabs at the top of a crag by the roadside 

 were riddled by burrows. Though, owing to the steepness of the 

 scarped rock, I could not actually reach these, I could see them 

 distinctly. I have no doubt that had I continued the search, I could 

 have found many more. Seeing, then, that I find my description of 

 the locality was substantially correct, and that these burrows are so 

 very abundant, both in Miller's Dale and Tideswell Dale, I am 

 unable to understand how it was that Mr. Brown failed to find them. 



In conclusion, I will add a few remarks on the general question 

 of the nature of these burrows. Some have supposed that these 

 holes are the result of weathering, either by fossils dropping out of 

 the matrix, or by the solvent action of carbonated water drilling the 

 rock — a process in some respects analogous to the formation of a sand- 

 pipe. Now, as to the former of these theories, I can only remark, 

 that in all the cases where I have found the burrows, fossils ai*e 

 conspicuous by their absence ; as to the latter, though it is true 

 that we often see forms not unlike them, and though in some of the 

 rocks in which they occur irregular semi-tubular hollows are com- 

 mon, — though, in a word, we occasionally get natural forms with some 

 resemblance to the burrows, — yet I think no one who has seen them 

 in large numbers can fail to be convinced that they cannot be ac- 

 counted for by any purely chemical theory. I believe, however, 

 that the burrower has sometimes availed itself of a previously ex- 

 isting depression. I may observe that so far as my observations at 

 present go, these burrows are usually found in a very pure homo- 

 geneous limestone, with a marly fracture and rather chalky surface, 

 but which is nevertheless very hard. So marked is this that I can 

 often tell from the appearance of a rock whether I shall or shall not 

 find burrows in it.' 



1 For example, during a brief visit to Cheddar last July, I did not come upon 



