Mr. Macgillivray's Account of the Outer Hebrides. ^t 



easy to determine whether the sand consists of fragments of the 

 shells which occur abundantly along the coasts at the present day, 

 or not, although the close inspection of it discloses nothing that 

 might indicate a different origin. Considerable quantities of un- 

 broken shells occur interspersed in it, often at great distances from 

 the shore. These entire shells belong to the Patella vulgata. In 

 some places the sand, in the vicinity of the shore, has become con- 

 crete, and in this state presents the appearance of a coarse-grained 

 sandstone. 



The violent gales of wind which frequently occur, scatter the 

 sand in all directions, and often to a great extent. The sand-drift 

 from the east coast of Pabbay, for example, passes over the island, 

 which is about a mile in breadth ; and the same takes place in 

 Berneray, where it comes from the west coast. By this drifting, 

 an intermixture takes places on the slopes of the hills with the peat 

 Soil that occurs there, forming compound soils of various fertility ; 

 and whenever there is the least proportion of sand, the vegetation is 

 obviously improved. Accordingly there is the greatest difference, 

 in point of vegetation, between the eastern and western sides of the 

 range. While the former are covered with heath and carices, the 

 latter present pasturages of great beauty, composed of numerous 

 species of the most nutritious plants. 



Sect. IV — Of the Vegetation, 



The circumstance that most strikes a person who visits these 

 islands for the first time, is the total absence of woods, and, as it 

 would appear to the superficial observer, even of trees. The bota- 

 nist, however, on searching the ruts along the course of the streams, 

 the rocky shores of the lakes, and the islands which the latter 

 frequently present, finds here and there a few diminutive speci- 

 mens of several of our more common trees. The species which I 

 have observed in such places are the following : Populus tremula, 

 Betula alba, Corylus Avellana, Alnus glutinosa, ana Pyrus Aucu- 

 paria. In the island of Lewis, not far from the manse of Keose, 

 there are the remains of a birch wood, the stunted bushes of which 

 occupy a considerable extent of ground. I have seen a few trees 

 of birch in the Forest of Harris about twenty feet high, and 

 many poplars from six to fifteen feet ; but these were merely shoots 

 from old roots which remained in the crevices of rocks. Pinus syl- 

 vestris had formerly grown in the Forest of Harris, where some of 

 its stumps still remain projecting through the moss, their roots be- 

 ing invariably in the subjacent clay or gravel. 



The other woody plants which occur are the follo^ring : Junipe- 

 rus nana, Rubus fructicosus, Rosa tomentosa, Lonicera Pericly- 

 menum, Vaccinium myrtillus. Arbutus Uva-ursi, Empetrum ni- 



frum, Calluna vulgaris. Erica cinerea, E. tetralix, JNIyrica Gale, 

 alix arenaria, S. repens, S. rupestris, and several other species. 

 Of the Juniperus, it is worth observing that, although abundant in 



