Hind : Carboniferous Geology. 



167 



Limestone Series, and the base of the Coal Measures, except in 

 Ayrshire, where the Coal Measures rest on the Carboniferous 

 Limestone. There is evidence elsewhere of volcanic activity 

 at this horizon. It is in this Millstone Grit Series that the 

 great change takes place from the Lower to the Upper Car- 

 boniferous flora, and about this horizon has recently been 

 found, by Mr. D. Tait, of the Geological Survey, an interesting 

 lamellibranch fauna, which I have described in the ' Tran- 

 sactions of the Royal Society', Edinburgh.' The important 

 fact revealed by this fauna is its relation to the fauna of the 

 Coal Measures of Xebrasca, U.S.A., and till this discovery, most 

 of the specimens had not been previously recognised in Western 

 Europe. This fauna has been traced through several counties 

 in Scotland. Since publication, one or two species have 

 occurred in the millstone grits of the Midlands. 



ISLE OF MAX. 



I have shewn that the Carboniferous successsion in the Isle 

 of Man f is to be referred to a few hundred feet of the L'pper 

 Dihimophyllum zone, and the base of the Pendleside Series. 

 The sequence is very similar to that which obtains in the Mid- 

 lands. The Poolvash Limestones and the black hmestones 

 of Scarlet, and the black marble quarry and their faunas can 

 be well matched by examples from Derbyshire, Staffordshire 

 and Yorkshire. 



IRELAXD. 



Very excellent work has been done by Drs. Matley and 

 Vaughan on the Carboniferous Series exposed from Rush to 

 Loughshinny. Their latest views are that the whole Series 

 represent Dihimophyllum beds, Cyathaxonia, and the Pendle- 

 side Series as high up as the horizon of Glyphioceras spirale.t 

 The palsontological reasons for this view are given at length : 

 but in addition, the thicknesses of the Series, mo feet, strongly 

 favours the correctness of this interpretation. 



Xo work on definite zonal lines has been carried out in the 

 south-west of Ireland, but certain facts are known. Prole- 

 canites compressus, the fossil which characterises the uppermost 



* Vol. XLVI., Part II., 15. T 



t ' 'Ir^tTts. Yorkshire Geol. See.', Vol. XXI., pt. 2, pp. 157-154. 



+ Q. J. Geol. Soc, Vol. XLIV., p. 434. 



1909 May I. 



