The Scottish Naturalist. 269 



fonn a hummocky grass field, becoming more level as the 

 distance from the bare pebbles is increased. The fore- 

 going ought to show us the possibility that all the land within 

 the thick broken lines on the map has been denuded and 

 restored — as I dare to assert it has — perhaps again and again. 

 Let us turn once more to the river's banks and we may see 

 more evidence of this. It ought now to be noticed that there 

 are two distinct heights to the denuded banks. One ranging 

 from 16 to 26 feet in height, the lower varying from 7 to 10 feet 

 above the level of the river. 



The lower "Haugh" generally forms the river's banks, but 

 occasionally the higher shows a bold front upon the river's side. 

 Upon examining a denuded part of the lower haugh the 

 first impression was that it consisted, except perhaps very 

 low down, entirely of the afore-mentioned arable loam. 

 There is, however, some slight evidence of stratification, and 

 further down the stream gravel bands come in at higher levels, 

 these merge into larger material and finally assume the dimen- 

 sions and appearance of a regular pebble-bed in every respect 

 similar to those now being formed by the river. This again 

 thins out, and other variously composed beds take its place. 

 There can then I think be no doubt of the fluviatile origin of the 

 lower haugh. As the modern pebble-beds become covered they 

 form a part of the alluvial tract 



The higher " Haugh," as has been seen, is being denuded at 

 a few points on the river's course. The first examination of 

 this was made at the southern extremity of the big curve below 

 C. At the top is about 1 foot of vegetable mould; below this 

 are 3 or 4 feet of, at least on the exposed surface, a slightly 

 indurated clay, with a conchoidal fracture. In this I could detect 

 no lines of stratification. Below this a band of carbonaceous 

 matter occurs, of 3 or 4 inches in thickness, that splits into 

 thin layers very easily. Below this again occurs a clay simi- 

 lar to that above, but indicating signs of horizontal deposition. 

 This alternates with layers of fine silt for about 8 feet, when 

 the clay disappears, and the silt passes into a bed of sand 4 feet 

 thick, with a few small well-rounded pebbles at the bottom. 

 This rests upon, and is clearly defined from, a bed of unctious 

 clay, consisting of alternate blue and red bands. This continues 

 down 1 2 feet, when it passes under the water. I counted nearly 

 40 of the alternate coloured bands in the 1 2 feet. 



(To be continued. ) 



