38 Notices of Memoirs — Dr. Le Neve Foster — Manganese Mining. 



Coniston Limestone, and indeed is intermediate in lithological character 

 between that Limestone and the Trinucleus Shales of Sweden. Palseon- 

 tologically it is connected with the latter by the occurrence within it of 

 Diplograptus like pristis, Dicellograptus anceps, Trinucleus seticornis, 

 Dindymene ornata ?, Cyhele Loveni, and Turrilepas. 



The Lower Coniston Flags have the fauna of the Cyrtograptus 

 Shales, though Cyrtograptus has not yet been found in them. Our 

 fossils are derived from near the base of this series, and that they occur 

 in beds about the horizon of the lower part of the Cyrtograptus Shales 

 is possibly indicated by the occurrence of Monograptus cidtellus, of 

 which, however, only one specimen has hitherto been found in the 

 Settle District. A further examination of these Lower Coniston Flags, 

 at points more remote from the base, will probably be rewarded by the 

 discovery of other species of Graptolites. 



That the Moughton Whetstones are really intermediate in position 

 between these Lower Coniston Flags and the flags in the quarries of 

 Arco Wood., Dryrigg, etc., seems proved by the occurrence in them of 

 Monograptus dubius, M. uncinatus? and M. Nihsoni, all of which are 

 found at the base of the Cardiola beds of Sweden, whilst the higher 

 parts of the Cardiola beds contain fossils identical with those of Arco 

 Wood, etc., including Monograptus colonus, and M. lohemicus. The 

 zone with M. duhius, etc., has, so far as I am aware, been hitherto unre- 

 corded in Britain, and the probable corresponding beds in the Lake 

 District are not of a nature suitable for the preservation of Graptolites. 



The Swedish affinities of these Settle rocks will probably be further 

 proved, when more work has been carried on in the district, and from 

 the simplicity of the sections, the area can confidently be recommended 

 to the notice of any geologist who wishes, by patient work, to assist in 

 establishing the zones of the Lower Palaeozoic rocks of our country. 



n^OTICIES OIP IMIIBnvIIOI^S. 



Papers read before Section C. {Geology) British Association Meeting, 

 Birmingham, 1886. 



I. — Manganese Mining in Meeionethshike. By C. Le Neve 

 FosxEE, D.Sc, F.G.S. 



MANGANESE ore is now being worked in the Cambrian rocks at 

 several places near Barmouth and Harlech. It occurs in the 

 form of a bed varying from a few inches to three feet in thickness ; the 

 average thickness is one foot to one foot and a half. The undecomposed 

 ore contains the manganese in the form of carbonate, with a small pro- 

 portion of silicate ; but at the outcrop it is changed into a hydrated 

 black oxide. Some of the outcrops of the manganese bed are erroneously 

 marked on the Geological Survey Maps as mineral veins, though Sir 

 Andrew Ramsay was of opinion that the deposits were not true lodes. 

 Eeeent wor'kings show plainly that the deposits are truly stratified 

 beds, or possibly various outcrops of one and the same bed, extending 

 over a considerable area. 



The ore contains from 20 to 35 per cent, of metallic manganese, and 

 is despatched to Flintshire and Lancashire for the manufacture of ferro- 

 manganese. The new Merionethshire mines are the first instance of 

 workings for carbonate of manganese in the British Isles. 



