48 NATURAL HISTORY SOCIETY OF DUBLIN. 



occurrence of Fossil Plants at the lowest part of the Carboniferous for- 

 mation in other countries, mentions that of a group of fossil Plants found 

 near Marwood, in Devonshire, at the base of the Carboniferous and top 

 of the Devonian. He then alludes to the Irish Plant localities of the 

 Yellow Sandstone group as occupying a similar position at the base of 

 the Carboniferous formation. Acknowledging the following informa- 

 tion, for which, he observes, we are indebted to Sir Eichard Griffith, 

 that "fossil Plants mark everywhere through Ireland the base of the 

 Carboniferous system," and after enumerating several Plant localities in 

 what is called the " Yellow Sandstone," or upper Old Red Sandstone, he 

 expresses his opinion that " the group of fossil Plants from these places, 

 by their resemblance to those of undoubted Carboniferous age, entitles 

 them to be classed with the Carboniferous deposits;" and that "in Ire- 

 land the base line of the lower Carboniferous period should be placed 

 below the entire group of Plant beds." I believe I have satisfactorily 

 identified the large Plant stems from Marwood, in North Devon, which 

 had been referred to Knorria, with Sagenaria Veltheimiana (of which it 

 appears to be a decorticated variety), a fossil so frequent at Kiltorcan, 

 Tallow Bridge, and many other places in Ireland, in rocks belonging to 

 both the Old Red Sandstone and Carboniferous formations, as well as on 

 the Continent, where it is, according to Dr. Geinitz, the most widely dis- 

 tributed fossil Plant in the oldest coal formation of Saxony. Dr. Goep- 

 pert, also, who includes Knorria imbricata and confluens amongst its 

 numerous synonyms, states it to have been found in the sandstone of 

 the "Upper Grauwacke 1 ' (query, Devonian), of Magdeburg, in Prussia, 

 and other places in Germany. Mr. J. Beete Jukes and Mr. J. W. Salter, 

 in their joint paper, * mention the occurrence of Plants under the name 

 of Knorria dichotoma and linear Plants in the "Yellow Sandstone," 

 which "forms the upper part of the Old Red Sandstone all along the 

 south of Ireland, from the Hook, in Wexford, to the shores of Bantry 

 Bay;" as also their occurrence at intervals throughout the Coomhola 

 grit in sandstone beds, overlying the Plant-bearing beds of Kiltorcan, 

 and identical with the Marwood beds of North Devon. 



The Carboniferous slate, on the south side of Kenmare Bay, extends 

 along the shore from Inishfarnard Island and Kilcatherine Point to Lehid 

 Harbour, continuing about half a mile inland from Ardea Castle to 

 Lower Clonee Lough ; and, according to the observations made by the 

 Government Geological Surveyors,! a section taken inland, near Kil- 

 catherine Point, shows a thickness of about 1500 feet, consisting of 

 grey compact grits (Coomhola grits), with a few thin beds of black slate. 

 Plant remains occur occasionally in the slates, often associated with 

 marine shells, corals, and crinoids ; and in the grit beds they are usually 

 found to be unaccompanied by any other description of fossils — the fossil 



* " On the Classification of the Devonian and Carboniferous Rocks of the South of 

 Ireland." — "Journal of the Geological Society of Dublin," vol. vii., p. 63. 



f Explanation to Sheets 197 and 198 of the Maps of the Geological Survey of Ire- 

 land. 



