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XIX. 



GEANITE, ELVAN, POEPHYEY, FELSTONE, WHINSTONE, 

 AND METAMOEPHIC EOCKS OF IEELAND. By G. H. 

 KINAHAN, M.E.I. A., Etc. 



[Read May 16, 1888.] 



INTEODUCTION. 



The eruptive and nietamorphic rocks were chronologically classified 

 by me in a Table accompanying Chapter xiii. of the " Geology of 

 Ireland " (1878) ; and on further research I find no reason for 

 material changes, although some minor modifications are necessary, 

 such as the proposed classification of these rocks in Antrim as 

 Eocene, on account of Mr. Starkie Gardner, Prof. Asa Gray, and 

 other American palaeontologists declaring that the plants found in 

 the associated tufTose beds [Iron measures) are of Eocene and not 

 Miocene types. The possible age of the exotic rocks of the S.E. of 

 Ireland is now given for the first time. With these modifications 

 the following Table has been brought up to the present state of 

 our knowledge. 



On account of the changes in nomenclature since 1878, when 

 the first Table was published, some of the names have to be altered 

 to those in the Table of Geological Strata, as given in these Pro- 

 ceedings, vol. v., page 204. 



In the following Table the 1st column indicates the different 

 formations with which the eruptive rocks are associated in Ireland. 

 In the 2nd column is given the general classification of the eruptive 

 rocks, to which metamorphic granite is added, so that it may be 

 seen in what formations and localities the gradual change from 

 unaltered, through metamorphic, into the eruptive rocks can be 

 best studied. The remaining columns give the districts, or 

 Territories, into which it seems most convenient to divide the 

 country. In them the sign * denotes the existence, the sign ? the 

 probable existence, of the rocks in the Territory indicated ; while 

 the columns are left blank when the rocks of the class are not 

 represented, or are supposed not to be represented. 



SCIEN. TROC. K.D.S. VOL. VI., PT. IV. P 



