9 16 Proceedings of the Royal Irish Academy. 



states, with reference to the raised beaches of the north-east of Ireland, that 

 the submerged peat under Estuarine Clay contains Pine, Oak, Hazel, 

 Alder, &c, and that the overlying or later deposits indicate a warmer 

 climate than that of the present time. Putting the various pieces of evidence 

 together, it would appear that the submergence of the land took place during 

 the transition period from Pine to Pine and Oak, and that the climatic 

 optimum, in which Oak predominated, came later, and prevailed towards the 

 close of the Neolithic Period. Clement Eeid supposes that the submergence 

 began in England about 5000 years ago, and occupied about 1500 years ; but 

 the data upon which this conclusion is based are not very clear. If the 

 opinion of the same author 1 be accepted, to the effect that the Oak would 

 require one million years to spread unaided from one end of the British Isles 

 to the other, the transition from pure Pine to pure Oak in the west of Ireland 

 would require a longer period than the geologist would allow, since the last 

 glaciation of the country. 



The origin of the townland names may be regarded as negative rather 

 than positive evidence ; but it is significant that all existing tree species are 

 perpetuated in these names, and the general omission of the Pine becomes all 

 the more significant. Joyce 2 suggests that the one or two instances in which 

 Pine is associated with townlands may refer to bog-timber rather than the 

 living tree. 



The occurrence of tree-stumps in or under mountain peat is not so well 

 marked as in the lowland or marsh bogs. In most cases they occur singly 

 or in small groups within a foot or so of the surface, and appear to have 

 grown on dry heath peat. Intermixed with this mountain peat, and merging 

 into it on all sides, are numerous shallow marsh bogs, and the stumps in these 

 may be several feet above the surface of the soil. While Oak is seldom 

 absent over large areas, it is evident that Pine is the predominant species in 

 this type of peat, and occurs up to elevations of 1500 feet in the Wicklow 

 Mountains, and down to sea-level in the west of Ireland, Birch being mixed 

 with it everywhere. Oak occurs up to 800 feet on Slieve Bloom ; but obser- 

 vations are lacking as to the exact altitude it attains in many parts of 

 Ireland. 



Whether in marsh or mountain peat, the occurrence of tree-stumps is very 

 irregular, thick groups and single trees being usually separated by spaces 

 free from stumps, and the general distribution is rather that of an open park- 

 like arrangement of the trees than that of a dense forest. The age of the 

 trees varies from 50 to 300 years or more, but, owing to the decay of the 



1 " Origin of British Flora." 2 " Irish Names of Places," vol. ii. 



