The Coniston grits east of Lune valley occur in a thick series of Ludlovian (Silurian) turbidites that is widely developed in south Westmorland and northwest Yorkshire, England. Contrary to the conclusion that the grits were derived from a land mass composed of the Borrowdale volcanic series (Ordovician) dividing the Lake District from southern Scotland, it is suggested that the Ballantrae series of the Cockburn land mass traversing the Southern Uplands from northeast to southwest was the source of the grit materials.