31 et seq.; also Evans, as cited in the previous chapter.

For the more recent investigations in the Danish shell-heaps, see Boyd Dawkins, Early Man in Britain, pp.

303, 304.

For these evidences of advanced civilization in the shell-heaps, see Mortillet, p.498.He, like Nilsson, says that only the bones of the dog were found; but compare Dawkins, p.305.For the very full list of these discoveries, with their bearing on each other, see Mortillet, p.499.As to those in Scandanavian countries, see Nilsson, The Primitive Inhabitants of Scandanavia, third edition, with Introduction by Lubbock, London, 1868; also the Pre-History of the North, by Worsaae, English translation, London, 1886.

For shell-mounds and their contents in the Spanish Peninsula, see Cartailhac's greater work already cited.