The lake-dwelling area thus surveyed comprises all the remains that can unequivocally be said to belong to the primary development of these structures in Europe, their period of existence being almost exclusively confined to the prehistoric ages of Stone and Bronze. Such being the case, this might be a suitable opportunity for offering some general remarks on the culture and civilisation of their inhabitants; but this I defer to the final lecture, thinking it preferable before doing so to acquaint my readers with various details of analogous remains brought to light in other districts in Europe. Accordingly in the fourth lecture we continue our geographical wanderings. Again starting in Switzerland we discuss the peculiar remains found in La Tène, almost the only exception to the ordinary _Pfahlbauten_ of the Stone and Bronze ages encountered in our previous tour; and thence, moving northwards by the lower Rhine district, we pass to North Germany, where we meet with settlements apparently belonging to all ages. The fifth lecture is exclusively devoted to an exposition of the crannogs and lake-dwellings within the British Isles. In these five lectures we have thus surveyed the entire area in Europe in which the remains of ancient lake-dwellings have been discovered in modern times. Excepting the well-known reports of Keller and a few monographs on particular stations or districts, the entire literature of the subject may be said to lie buried in the Transactions of learned societies. Having to hunt up and peruse most of these obscure and almost inaccessible articles--the number and extent of which may be estimated by a glance at the accompanying bibliography--it occurred to me that, by tabulating all the works and notices of these researches in chronological sequence, under the names of their respective authors and with correct references to their published sources, I might be conferring some benefit on future investigators, while supplying myself with a simple and ready means of referring to authorities, without the necessity of having to repeat over and over again the voluminous titles of publications. Hence the origin of the bibliography appended to this work, which, however imperfect, will, I trust, considerably enhance its value. Its compilation has given me a great deal of trouble, and the only valuable assistance I derived from other publications of the kind was from Pigorini's "Bibliography of Italian Archæology," which, unfortunately, comes down only to 1874. There remains now only the pleasant duty of thanking those who have assisted me in bringing the work, so far, to a satisfactory conclusion. On this score my obligations are very great.