Arber — The Flora of the Bally castle Coalfield. 163 



Professor Cole, and on behalf of the G-eological Survey of Ireland, I also paid 

 a short visit to Ballycastle, in June, 1911, to examine the coalfield, and to 

 collect additional examples of its flora. The few specimens which I was able 

 to obtain are also described here. They are now incorporated in the Irish 

 Survey collection. 



It is not proposed to discuss here the geology of the Ballycastle coalfield. 

 This subject has been treated of in detail by Berger and Conybeare (1816), 

 Bryce (1837), Sir R. Griffith (1829), Professor Hull (1871 and 1877), and in 

 the Survey Memoir on the district in question (1888).' Some of these papers 

 will be again referred to in connexion with the fossil plants. The dominant 

 lithological types of the Carboniferous sequence at Ballycastle are soft, coarse- 

 grained, red, yellow, or white sandstones, and black shales. The subsidiary 

 beds consist of thin seams of coal, with thin bands of argillaceous limestone 

 and clay ironstone, both in the form of nodules and bands. The entire 

 thickness is stated by Hull to exceed 1,200 feet. As is well known, this 

 coalfield is intruded by a large lacoolite of dolerite, which in places covers 

 the Carboniferous rocks. A similar state of affairs is met with at Glee Hill 

 in Shropshire. 



At the time of my visit to Ballycastle the opportunities for collecting 

 fossil plants proved to be very unfavourable, though the rocks are well 

 exposed on the coast in the cliifs on either side of Fair Head. I found that 

 the black shales rarely contain any plant-remains, except the rhizophores and 

 rootlets of Stigmaria, which are abundaut. Some beds, however, are rich 

 in mollusca. The soft, coarse-grained sandstones are, for the most part, 

 unfossiliferous, though very occasionally they yield plant-remains. These 

 consist chiefly of large, somewhat rough impressions or casts of stems or 

 branches of Lepidodendron, or of its rhizophore, Stigmaria. At the time of 

 my visit all the collieries and other workings for coal had been abandoned 

 for some years, and thus one likely source of material was no longer available. 

 On the western side of Fair Head, however, between Ballyvoy Pier and the 

 Oarrickmore Dyke, there are two or three sandstone quarries in the eliiis, 

 containing a large amount of loose, discarded blocks. These are usually 

 barren, though now and again they contain casts of the type above indicated. 

 It was chiefly from these, and from the old waste heap of White Mine 

 Colliery, closed a few years ago, that I was able to collect the few specimens 

 described here. A search of the exposed area of Carboniferous rocks on the 

 eastern side of Fair Head, at Fall Point, proved fruitless so far as fossil 

 plants were concerned. I also endeavoured to locate the spot on the western 



' For references to these papers, see the Bibliography on p. 175. 



2£2 



