SHELL-HEAPS, or KITCHEN-MIDDEN (Dan. Kjokken-modding), prehistoric refuse heaps or mounds found in all quarters of the globe, which consist chiefly of the shells of edible molluscs mixed with fragments of animal bones, and implements of stone, bone and horn. They may sometimes, as in the Straits of Magellan, be seen in process of formation. Many having a prehistoric origin have been examined, notably on the eastern coast of Denmark. These were at first thought to be raised beaches, but a cursory examination at once proved their artificial construction. Further investigation by archaeologists proved these shell-heaps to belong to a very ancient period, probably the early part of the Neolithic age, " when the art of polishing flint implements was known, but before it had reached its greatest development " (Lord Avebury, Prehistoric Times, 6th ed. p. 235). They contained the remains of quadrupeds, birds and fish, which served as the food of the prehistoric inhabitants. Among the bones were those of the wild bull or aurochs, beaver, seal and great auk, all now extinct or rare in this region. Moreover, a striking proof of the antiquity of these shell-heaps is that they contain full-sized shells of the common oyster, which cannot live at present in the brackish waters of the Baltic except near its entrance, the inference being that the shores where the oyster at that time flourished were open to the salt sea. Thus also the eatable cockle, mussel and periwinkle abounding in the kitchen-middens are of full ocean size, whereas those now living in the adjoining waters are dwarfed to a third of their natural size by the want of saltness. It thus appears that the connexion between the ocean and the Baltic has notably changed since the days of these rude stone-age peoples. The masses of debris were in some places ten to twenty feet thick and stretched a thousand feet. It does not appear that the men of the kitchen-middens had any knowledge of agriculture, no traces of grain of any sort being found. The only vegetable remains were burnt pieces of wood and some charred substance, possibly a sea-plant used in the production of salt. Flat stones blackened with fire, forming hearths, were also found. That periods of scarcity must have been frequent in the absence of cereals is indicated by the discovery of bones of the fox, wolf and other carnivora, which would hardly have been eaten from choice. The kitchen-middens of Denmark were not mere summerquarters: the ancient fishermen appear to have stayed in the neighbourhood for two-thirds, if not the whole, of the year. This is suggested by an examination of the bones of the wild animals, from which it is often possible to tell the time of year when they were killed. Thus the remains ofthewildswan (Cy gnus musicus), a winter visitor, leaving the Danish coast in March and returning in November, are found in abundance. Additional proof is afforded among the mammalian remains by two periodical phenomena, the shedding of the stag's antlers and the birth and growth of the young. The flint implements found include flakes, axes, awls, sling-stones or net-weights, and rude lanceheads. A fragment of one polished axe was found at Havelse which had been worked up into a scraper Small pieces of coarse pottery are also met with. The Danish kitchen-midden men were not cannibals. In physique they seem to have resembled the Lapps, a race of small men with heavy overhanging brows and round heads. The excavation of the Danish shell-heaps 'was followed by the investigation of others in other countries. At Omori (Japan), in the Aleutian Islands, in British Columbia, Oregon and California shell-mounds were explored, always with the result of proving that the present populations had been preceded by ruder tribes of great antiquity. On the Atlantic coast of Brazil shell-heaps, which must have taken thousands of years to accumulate, are now overgrown with dense forests.
BIBLIOGRAPHY. Paul Schumacher, Kjokken-moddings on the Northern Coast of America (Smithsonian Reports, 1873); E. Reclus, The Earth and its Inhabitants (New York, 1890), vol. xix. ; D. G. Brinton, Artificial Shell-deposits of the United States (Smithsonian Reports, Washington, 1866); Lord Avebury, Prehistoric Times (6th ed., 1900); J. Wyman, "Fresh-water Shell-mounds of Florida," Memoirs of the Peabody Academy of Sci. vol. i. (Salem, Mass., 1875); Morse, Shell-mounds of Omori (Tolcio, 1879); F. H. Gushing, Ancient Key-Dwellers' Remains (Philadelphia, 1897); W. H. Dall, Tribes of the Extreme North-West: Contributions to North American Ethnology, vol. i. (Washington, 1877).
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)