Correspondence. 233 



and now my friend conseaits to have them figured and described by 

 our best authorities. So I must invite geologists, if not Mr. Pengelly 

 himself, to find for us what shells, corals, etc., occur with these 

 actual specimens. They do indeed appear to lie in the lowest beds ; 

 but there is the possibility, I have above hinted at, of the Upper 

 beds overlapping unconformably round the south coast, where 

 hitherto we have not known them. Near Teignmouth, indeed, we 

 have the Upper Devonian beds ; and my note-book tells me there is 

 a fault (one out of many in this district) between the Meadsfoot 

 sandstones with Lower Devonian shells, and the pile of grey rocks 

 which hold this fish-scale ; and unconformity and faults will do any- 

 thing but mix the fossils in the bed itself, especially in S. Devon. 



But Looe Island with the fish, is not Looe with its Lower Devonian 

 shells; and Meadsfoot fish-bed has not yet been proved to be the 

 same beds as those which hold the trilobites and shells. Here is 

 work for the local geologist ; and as asking about the fish has pro- 

 duced so much, I hope asking about the geology "vidll do more. We 

 want now to know what are the exact relations of the beds which 

 hold these fish : for fish they are — the only ones (the N. Devon one 

 was a mistake) known in British Devonian rocks. — J. W. S. 



BALA AND HIRNANT LIMESTONE. 

 To the Editor of the GEOLoaiOAL Magazine. 



Sir, — There is a point of much interest to be worked out in North 

 Wales : viz., the exact relation and age of the upper or Himant 

 limestone of Bala. 



Some of the fossils in this remarkable band are known. It is 

 the only example (so far as I know), in rocks below the Wenlock 

 limestone, of a pisolitic structure ; very marked in the neighbour- 

 hood of Bala. But beyond Bala, etc., it is not at present known. 



I beg to suggest an excellent piece of work for one of the Clubs 

 this year (unless Mr. Davies, of Oswestry, means to do it single 

 handed). It is to work out thoroughly the geology of one mountain, 

 close to Llangollen, and therefore easily accessible. If they would 

 examine Mynydd-Fron-Frys, which is not a lofty one, and has good 

 roads all round, it will be much better service than making what is 

 called a section or a traverse. There are two beds of limestone 

 there : — the Bala limestone, and an upper one, probably, the 

 " Himant " limestone ; and from this locality some of the very 

 rarest of our Bala fossils have been obtained. 



There is a huge Loxonema there, six or seven inches long ; a fine 

 Lituites, viz., L. anguiformis, — the only specimen known in Britain, 

 yet, is that in the Woodwardian Museum. Then, again, there is a 

 species, probably new, of Bumastus to be found ; and such a crowd 

 of Corals, Bryozoa, and other choice things, that it is like working in 

 a museum ; I had but two hours for it all. 



Now what we want to know is the exact contents of each of these 

 bands of limestone ; for one is probably very different from the 

 other. And if the above rare fossils are from quarries in the upper 



