Widespread over England and Wales there are superficial deposits of a structureless and rubbly character that can be classed neither with true glacial deposits nor with river drifts. These are especially noticeable beyond the southern limit of glaciation, but they also occur, with less frequency, within the glaciated regions. Geologists in the early part of the last century, unhampered by pre-conceived ideas, frequently described such deposits, and in 1839 De la Beche, probably adopting a quarryman's term for overburden, gave certain occurrences the name Head. In later years Pleistocene classification, embracing both glacial and river drifts, took little or no account of these apparently irregular accumulations. Only those cases that presented special characters or were extensive and thick were shown, under a variety of names, upon geological maps.