246 TRANSACTIONS, NATURAL HISTORY SOCIETY OF GLASGOW. 



with the narrow pass beyond Loch Libo ; and on the 

 east a low ridge separates the Lugton drainage from 

 that of the Garnock and Aimick, which belong to 

 the Irvine Valley. 



In the southern part of the district, south of 

 Kilwinning and onwards to the sea, the land is 

 either sandy or consists entirely of drifted sand. 

 Along the courses of the principal streams there are 

 considerable tracts of alluvial soil ; especially in the 

 part of the course of the Garnock extending from 

 Dairy to Kilbirnie, which is about half a mile wide 

 and evidently occupies the position of an ancient 

 filled-up lake ; along the Caaf Water, at that part 

 called Holms-of-Caaf ; and on the Lugton, at Lugton- 

 ridge and north of Waterland, apparently occupying 

 ancient lacustrine sites. A few similar patches of 

 alluvial soil occur along the courses of the Dusk, 

 Bombo, and Rye Waters ; but the great bulk of the 

 cultivated soil is composed of improved boulder- 

 clay. 



The Garnock, which is the principal river in the 

 valley, rises between Stake and East Girt Hills, 

 respectively 1,711 and 1,673 feet in height, and for 

 the first five miles its course runs over rocks of 

 porphyrite and of volcanic agglomerate. The portion 

 of the bed of the river between the Falls of Garnock 

 and Glengarnock Castle is in many places very fine, 

 being fantastically sculptured into smooth rocky 

 pools. The scenery around the falls is highly 

 romantic. A short distance below the falls the river 

 receives on the left a small tributary which descends 

 from Misty Law, and on the right the Surge Burn 

 which flows from High Corby Knowe, a hill 1,615 feet 

 above sea-level. In the lower part of its course, the 

 latter stream cuts through thick boulder clay capped 

 with a deep bed of peat-moss, which is the usual 

 covering of the moors throughout the district. 

 Away to the left of the Garnock, two miles 

 from Misty Law, stretches Ladyland Moor with 

 porphyrite hills rising respectively to the height of 



