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XLI. 



ON THE FAUNAL ZONES OF THE EUSH-SKERRIES 

 CAEBONIFEIiOUS SECTION, CO. DUBLIN. 



By LOUIS B. SMYTH, B.A., B.Sc, 

 Lecturer in Palseontology, University of Dublin. 



(Plates XXXV-XXXVIL) 



[Bead May 18. Published August 13, 1915.] 



Introduction. 



This section has been excellently described by Dr. C. A. Matley in two papers 

 published in 1906 and 1908 respectively.' At the same time an account of the 

 faunal succession and correlation was given by Dr. Arthur Vaughan. The 

 material with which Dr. Yaughan liad to work was, for the most part, scanty 

 and fragmentary, and his conclusions are in many cases put forward only 

 tentatively, pending further evidence. This is especially the case with the 

 parts of the section dealt with in this communication. 



The present work was undertaken at the suggestion of Dr. Vaughan. Its 

 principal object has been to accumulate more and better fossils, and thus to 

 settle the outstanding questions of correlation. 



Several things make this a difficult locality to deal with. The deposits 

 were formed near a shore line, so that the fossils are usually very imperfect. 

 Many of the rocks can only be reached for a short time at low tide, and are 

 covered with seaweed. The section is broken up by gaps and faults, and the 

 rocks are much folded, and, in places, cleaved. 



The section occurs at the western extremity of the laud barrier which, 

 in Lower Avonian time, separated the Bristol- Dinant Gulf from the waters 

 which deposited the northern and midland rocks. 



The same horizons occur in the northern and southern parts of the section 

 in different phase, the northern rocks containing scarcely any fine-grained 

 detritus ; whilst slates and shales are characteristic of the southern outcrop. 



1 Quart. Journ. Geol. Soc, vol. Ixii, 1906, p. 275, and vol. ixiv, 1908, p. 413. 

 SCIENT. PROC. R.D.S. , VOL. XIV., NO. XLI. 4 B 



