OF THE BASALTIC FORMATION OF ULSTER. 91 



To set against these positively recorded observations, there is 

 only the opinion that the wood may have been derived from beds 

 included among the basalts which might be found in situ ; but the 

 only wood hitherto so found at all resembling that of Lough Neagh is 

 in the state of oxide of iron, and belongs to Pinus, while the whole 

 of a large series of Lough-Neagh woods examined with me by Mr. 

 Carruthers is Cupressineous. The evidence, fairly weighed, seems 

 altogether in favour of the interbasaltic age of the Lough-Neagh beds ; 

 and my own opinion now is that they are of much the same age as the 

 Ballypalady and other fluviatile deposits to the north, and that they 

 will be found to continue under some of the lavas. A thorough inves- 

 tigation of the palseontological evidence can alone, however, remove the 

 question from one of inference to one of fact. [Mr. Hardman main- 

 tained the age of the Lough-Neagh beds to be very recent (Geol. Mag. 

 1879, p. 216), but his arguments appear purely negative. He 

 assumed that Barton's stony wood was pyritized, that Griffiths's section 

 at Sandy Bay transposes the clay and lignites, that the deposition of 

 the clays was posterior to the faulting and denudation of the basalts, 

 that the real lociis of the silicified wood is the basaltic lignites, &c. 

 He also points to differences between them and the bed at Ballypalady; 

 asks why, if they were there in basaltic times, the basalts did not flow 

 over them ; and illustrates his reading by two ideal sections in oppo- 

 site directions across the lake (Journ. Geol. Soc. Ireland, vol. iv.). 

 If these assumptions and sections were correct, his interpretation 

 would be the right one ; but otherwise the lithological difference is 

 not greater than between the interbasaltic formations of Ballypalady, 

 Glenarm, and Mull.] The Lough-I^eagh beds seem to have been 

 formed near the southern limits of the basalt-flows, which are 

 vesicular at Shane's Castle ; but they are in all probability to some 

 extent overflowed and concealed by trap towards the east. 



The nodules containing the plant-remains are usually found on 

 the shores of Sandy Bay only when the level of the Lough is low ; 

 though, in company with Mr. Swanston, we obtained an iron- 

 stone nodule with leaves in the Boulder-clay from the bank, and 

 two others from the bed of the Glenavy river. The plants 

 these contain are most diversified, though usually small-leaved 

 dicotyledons which at first sight seem of very modern aspect. On 

 closer examination, however, many are found to be characteristic of 

 the English Middle Eocene, and others of the Lower Eocene. Others 

 are common to Ballypalady, to MuU, and to Greenland. This 

 mixture of types, so separated elsewhere, would be difficult of 

 explanation, did the thickness of the deposit not warrant the belief 

 that it may have been continuously forming throughout more than 

 one period of the Eocene. Most of the plant-remains come probably 

 from the higher horizons now exposed on the shores of the Lough ; 

 but some of those from the Boulder-clay may come from much 

 lower horizons in it. The flora, however, is by far the most 

 important link yet discovered between the Eocenes of England 

 and those of high northern latitudes, and as such is deserving of 

 most attentive study. 



