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VOLUME XII. 



RECENT PAPERS RELATING TO IRISH GEOI.OGY. 



BY PROFESSOR G. A. J. COI^E), F.G.S. 

 BI,UE AMPHIBOI.E:. 



Mr. H. J. Seymour describes a secondary blue amphibole, 

 occurring as an outgrowth from primary green hornblende 

 in a dyke of kersantite from Co. Down. The dyke lies three 

 miles south-east of Portaferry. Occasionally the blue material 

 replaces the original hornblende, and the occurrence is of 

 interest as forming the first record of blue amphibole in situ 

 in Ireland {Geol. Mag., 1900, p. 257). 



THE NORTHERN " FEI.STONES." 



Prof Cole and Mr. J. A. Cunningham, A.R.CScI., describe 

 several rocks occurring as dykes in Co. Donegal {Sci. Proc. 

 R. Diibliii Soc, vol. ix., 1900, p. 314), and hitherto known as 

 "felstones." These prove to be mostly lamprophyres, as Dr. 

 Hyland had already indicated ; a dyke of vogesite was dis- 

 covered by Mr. Cunningham near Drumboy, and must be 

 added to those upon the Survey map. The authors give 

 reasons for assigning a Devonian age to these dykes through- 

 out northern Ireland. 



OLDHAMIA AND HISTIODERMA. 



Prof SoUas's detailed paper on the antique genus Old- 



hainia and a new genus Ichiiiuvi from Co. Dublin {Qiiart. 



Joiirn. GeoL Soc. LondoUyVoX. ivi., 190O; p. 273), has been already 



discussed in this Journal (vol. x., 1901, p. 81). Mr. G. F. 



Matthew, of the Canadian Survey, contributed some informa- 



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