A section at Lenham Hill about 1 km north of the village of Lenham in Kent exposes solution pipes in the Chalk that contain detached blocks of fossiliferous sandstone. Prestwich (1855) noted the irregular position of the cemented blocks and described the process of pipe formation. These so-called ‘Lenham Beds’ yield decalcified mollusc shells preserved as moulds, and also occasional examples of lunulitiform bryozoans identified in the old literature as Lunulites but indeterminate.
Overall the fauna of the Lenham Beds resembles that of the East Anglian Crags, and was postulated by Prestwich to be equivalent in age to the Coralline Crag, or perhaps older. However the exact age of the Lenham Beds remains unknown, and the environment of deposition and the mechanism by which they came to be preserved within solution pipes is as yet unresolved.
Localities which expose solution pipes containing fossiliferous sediments of the Lenham Beds include Pivington Quarry (TQ 915525) and Hart Hill (TQ 943506), both in Kent.