15 Rutimeyer: “Fauna der Pfahlbauten in der Schweiz.” 16 _Anzeiger für Schweizerische Alterthums Künde_, April, 1884. 17 Comte Conestabile: “Sur les Anciennes Immigrations en Italie.” Heilbig: “Beitrage zur Altitalischen Kultur and Kund Geschichte,” i. Band. G. Boissier: _Révue des Deux-Mondes_, October, 1879. 18 _Bul. di Palethnologia Ital_., 1879. The _terpens_ of Holland, though of much more modern date, greatly resemble the _terremares_. 19 “Ricerce di Archeologia Preistorica nella Valle della Vibrata.” 20 Wylie, _Arch. Brit_., vol. xxxviii. Wylde, _Proc. Royal Irish Acad_., vol. i., p. 420. 21 _Arch. Brit_., vol. xxvi., p. 361. _Proc. Royal Irish Academy_, vol. vii., p. 155. 22 “Habitations Lacustres des Temps Anciens et Modernes,” p. 170. 23 R. Munro: “Ancient Scottish Lake Dwellings or Crannoges, with a Supplementary Chapter on Remains of Lake Dwellings in England,” Edinburgh, 1882. 24 “Prehistoric Times.” Wilson: “Prehistoric Scotland.” 25 Nicolucci: “Scelse Lavorate, Bronzi e Monumenti di Terra d’Otranto.” Lenormant, _Revue d’Ethnographie_, February, 1882 (_Bul. Soc. Anth_., 1882 and 1884). S. Reinach: “Esquises Archéologiques.” 26 “Les Premiers Âges du Métal dans le Sud-Est de l’Espagne,” Brussels, 1887. CHAPTER V. Megalithic Monuments. Megalithic monuments are perhaps the most interesting of all the witnesses of the remote past, into the history of which we are now inquiring, and of which so little is known. From the shores of the Atlantic to the Ural Mountains, from the frontiers of Russia to the Pacific Ocean, from the steppes of Siberia to the plains of Hindustan, we see rising before us monuments of the same characteristic form, built in the same manner. This is a very important fact in the history of humanity, and of which it is difficult to exaggerate the importance. What is the age of all these monuments? Were they all erected by one race, which has thus carried on its traditions front one generation to another? Were they the temples of the gods of this race, or the tombs of their ancestors? Did the people who set them up come from the East, or did they come from the North, on their way to the warmer regions of the South? These and many other questions are eagerly discussed, but in the present state of our knowledge not one of them call be answered in a perfectly satisfactory manner. _Scire ignorare magna scientia_, said an ancient philosopher, and this is a truth which we must often repeat when we are dealing with prehistoric times. [Illustration: 55.] Dolmen of Castle Wellan (Ireland).