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of shells of a deep sea character, and which beair such a similarity to the shells 

 of the Mountain Limestone below, that I look upon them as a sort of transition 

 bed. Another curious and suggestive fact is, that in all the sections there is no 

 mention made of any imderclay to these veins, while above — even in the Pennant 

 rock — there is no coal without it. In the coal seams I have found wings of 

 insects ; something very like the body of a dragon fly ; another nondescript like 

 a small paddle with five toes — lingula, leptjena, producta and conularia (perhaps 

 quadrisulcata). In a small measure of ironstone, at the very head of the dingle, 

 I have obtained 



Productus giganticus and another species. 



Rh5mconeUa. 



Leptaena tenuistriata and one other. 



Terebratula. 



Spirifer, three or four varieties. 



Strophomena depressa and another sort. 



Lingula mytiloides, and another sort. 



Orthis. 



Donax sulcata. 



Nucula acuta. 



,, aequalis. 



„ accipiens. 

 Pecten scalaris. 



„ gentUis. 

 Mytilus triangulairis. 

 Modiola. 

 Unio aquilinus. 

 ,, robustus. 

 Bellerophon hiulcus, and two other varieties. 

 Nautilus. 

 Littorina obscura. 

 Goniatites Listeri. 

 Turritella minima. 



and another variety so small that it is impossible to make it out without a 

 magnifying glass. All these shells are in ironstone and ferruginous clay, and some 

 of them — especially the smaU ones — glitter like gold with their polish of iron 

 pyrites. 



After considering all these different measures and their remains, the truth of 

 what Sir R. Murchison says is very evident. He says : "In geology, less indeed 

 than in other sciences, can we ever hope to account for certain rssults by one 

 ' modus operandi ' only. For natmre seems to have worked out phenomena 

 apparently similar, through distinct paths, and by devious processes and of this 

 no clearer proof can be given than that coal was formed out of vegetables, which 

 were accumulated by at least two methods." 



