250 THORODDSEN 



often occurs above the clay, and then more recent river-deposits, 

 alternating with mohella, volcanic gravel, etc. Here and there, these 

 formations are exposed at the surface and form an almost barren 

 gravelly flat (melar), which, far into spring, is quite slushy, owing 

 to the melting snow, which cannot drain away on account of the 

 sub-surface ice and the clayey subsoil. In the eastern part of the 

 southern lowland tract, under the boggy ground, occur enormous 

 river-deposits (Landeyjar) delta formations from Markarfljot and 

 other rivers. But higher up, where the soil is drier (Rangarvellhj, 

 the subsoil is composed of thick mohella-formations; nearer to the 

 sea occur fine sand and downs. 



In several districts in the lowlands there are a great many 

 rocky ridges (holt), which protrude through the morasses and grass- 

 land. They vary in nature according to the character of the underlying 

 rock, and generally consist of basalt or dolerite, rarely of palagonite- 

 breccia. These ridges usually bear clear evidence of the action of 

 the glaciers during the Ice Age. They are highly ice-striated and 

 often have two distinct sides, one bearing traces of having been 

 exposed to the direct force of the ice, while the leeward side is 

 comparatively destitute of such marks. Their external form is some- 

 times dependent upon the direction of the inclination of the basalt- 

 layers. In some places (Myrar and Breidifjor5ur) they originate from 

 fragments of a deeply sunk basal rock. The surface is usually stony, 

 with solid rocks, larger loose stones, and smaller gravel; sometimes 

 a great many erratic blocks are scattered upon the ridges. As re- 

 gards plant-growth, these ridges should be characterized as rocky 

 flats more or less covered with vegetation, and protruding like small 

 islands above the grass-covered, usually boggy level lands. In several 

 places the ridges, in olden times, have been clothed with coppice 

 woods, but it is centuries since the coppice has been destroyed by 

 sheep and goats. Such ridges are found scattered over a great part 

 of the island in the lowlands and valleys, and often impart a cha- 

 racteristic feature to the landscape. The farm-buildings are often built 

 upon them. In the low-lying marshy land of Myrar, at the edge of 

 Faxafloi, they occur scattered in hundreds in the bogs, and in the 

 southern lowland district they are frequent in the eastern part of 

 Floi and the upper part of Holt, while elsewhere large stretches of 

 this lowland area are completely flat. In other districts they are 

 so large that they are most properly described as small moun- 

 tains (fell, halsar). In the valleys the old moraines are often trans- 



