THE PREHISTORIC PERIOD THE county of Hertford is fairly rich in the remains of the prehistoric, or, as it may perhaps in this instance be called, the pre-Roman period. In treating of it, it will be well to adopt the usual subdivisions of the Palaeolithic, Neolithic, Bronze and late-Celtic periods, and, in addition, to call attention to some of the more remarkable earthworks in the county, though the age of many of them is uncertain, and may possibly be post-Roman. In giving summary notices of the various discoveries, references will in most cases be made to the works in which more detailed accounts of them may be found. THE PALEOLITHIC PERIOD When first, about the year 1859, special attention was called to the discovery in the gravels of the valley of the Somme at Abbeville and Amiens of implements of flint evidently fashioned by the hand of man, it was soon perceived that they must belong to a far earlier time than the better-known weapons and implements of the Stone Age as defined by the Scandinavian school of archaeologists. Not only did these drift-implements occur associated with a fauna different from that now prevailing in western Europe, but their forms and the character of their workmanship were also different. Many of the animals whose remains are found in the implement-bearing gravels, such as the TLlephas primigenius, or Siberian mammoth, and the Rhinoceros tichorbinus, or woolly-haired rhinoceros, are now absolutely extinct ; while others, such as the reindeer, are now only found in latitudes farther north. Among the mollusca in the beds in which the implements are found, some are also extinct, while others occur only in distant habitats. The Corbicula fluminalis or Cyrena consobrina, which is of not unfrequent occurrence in the implementiferous beds, is now no longer living in any river nearer than the Nile. Instead, moreover, of being usually found upon the surface of the ground, at a moderate depth below it, or in graves or burial mounds, the new class of implements was often and indeed generally discovered in undisturbed beds of loam, sand, and gravel of considerable thickness, and principally towards the base of such beds. And further, these deposits in which the implements were found pre- sented the appearance of having been laid down by flood-waters in the valleys of ancient rivers, which in the course of ages had been deepened 223
