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ON SOME TRAILS AND HOLES FOUND IN ROCKS 



SO far as I am aware, little has yet been done in it with the 

 exception of the investigation of the origin of ripple marks 

 upon flagstones. This has excited considerable interest, and 

 it is now pretty well determined that these appearances, 

 although more frequently indicating the former existence of 

 sea beaches and beds formed in shallow water, are by no 

 means to be confined to those conditions, as they have been 

 found in the present seas under several hundred feet of water. 

 Your attention will chiefly be requested to the trails of the 

 former inhabitants of shells and worms, as well as the bur« 

 rowings of the latter, made on and in the rocks, when they 

 were in the state of soft sand or mud ; but some observations 

 will also be made upon those common annelids which have 

 long passed for molluscs, and were known by the name of 

 microconckus carbonarius. 



The above-named humble memorials of the fauna of the 

 carboniferous epoch must at present suffice for our con- 

 sideration. There is little doubt, however, but that rep- 

 tilian remains will be found amongst the coal measures in 

 England, like those of Germany and the United States of 

 America. The tracks and trails as yet met with in these 

 rocks give no indication of having been made by reptiles, like 

 those found in the new red sandstone of Weston, Cheshire, 

 and other places, as well as the old red sandstone of Scotland. 

 In my cabinet is a vertebra from the roof of the Riley Coal 

 at Captain Fold, near Heywood, which the most celebrated 

 living comparative anatomists cannot distinguish from the 

 caudal vertebra of an ichthyosaurus. As, however, no other 

 bones were met with in that locality, doubts have been raised 

 as to the authenticity of the specimen ; but as to its having 

 really been found in the place where it was represented to 

 have come from, there is quite as much evidence as of 

 three-fourths of the fossil remains which are labelled in 

 cabinets. 



Most of the trails and marks found upon the rocks of the 



