December, 1904- Prakge;r. — The Flora of A chill Island. 277 



The principal effect of the shelter thus produced is to increase 

 greatly the number, but not the variety, of certain native 

 plants, notably ferns and brambles. On the hill behind 

 Sraheens Lough, on the outskirts of these woods, the result 

 of the shelter and of the absence of grazing and heather- 

 burning is that several native trees, some of them not found 

 elsewhere in Achill, here put in an appearance and grow to a 

 good size. Betula pubescens and Pyfus Ancupa?ia are quite 

 abundant, and with them are Qicercus, Ilex, Cory 1ms y and Almis. 

 Near the Sound the introduced trees and bushes include several 

 kinds of Poplar, Salix pentandray 6*. fragllis, S. S^Jiithiana^ 

 Pfunus Cerasus, Rosa rtcbiginosa, and others. Patches of S. 

 vi7ni7ialis are grown in many places for basket-making. 

 Generally no attempt whatever is made to plant shelter-trees 

 about the cottages ; but occasionally in the east a few stunted 

 Elders or Poplars may be seen so used. 



Alpine Ground, 



The summit floras of the highest points of Achill (Slieve- 

 more, 2,204 feet ; Croaghaun, 2,192), have already been listed 

 when dealing with the moorland flora. On Slievemore, a 

 rocky escarpment facing north runs up the hill almost from 

 base to summit. The upper end of this scarp presents good 

 alpine ground — several hundred feet of hard dripping gneiss. 

 Here Sedutn Rhodiola^ Saxifraga stellar is^ and Cystopteris 

 fragilis grow in great profusion. More locally plentiful is 

 Oxyria digy7ia, not previously recorded from Achill ; but the 

 most interesting plant of Slievemore is Epilobium a7igtisti- 

 folitwz, which occupies a grassy ledge at about 1,900 feet, with 

 Geufn rivale. This is a characteristic plant of Ulster, with 

 outlying stations in the Wicklow and Sligo-Ivcitrim highlands. 



Croaghaun presents a grand precipice nearly 2,200 feet high, 

 facing north-west, and plunging right into the Atlantic. The 

 similarity of conditions here to those prevailing at the 1,500- 

 foot cliff on Clare Island, which yields so interesting an alpine 

 flora, led me to have hopes of Croaghaun in this respect. But 

 here a disappointment awaits the botanist. The Croaghaun 

 scarp yields, as regards highland plants, only Saxifraga stel- 

 lariSi Sedu7n Rhodiola^ Salix herbacea^ and Carex rigida. The 

 explanation is to be found, I think, in the nature of the rock. 



