GEOLOGY OF THE VEZERE. 27 



in. 



SKETCH OF THE CHIEF GEOLOGICAL FEATURES OF THE VALLEY OF THE VEZERE 



AND THE BORDERING COUNTRY*. 



THE Caves and Bock-shelters containing the Aquitanian relics treated of in this 

 Work are, as already described (pages 3 and 20), excavated in cliffs of limestone 

 along the lower portion of the Vezere. A considerable extent of country 

 traversed by this part of the river, in a N.E.-S.W. direction, from near Condatf 

 to Limeuil, where the Vezere joins the Dordogne, and by the latter river to 

 La Linde, and seven miles beyond, is composed of stratified limestones, thinly 

 capped, here and there, by patches of clays, sands, ironstone, and gravel (see Map, 

 p. 29). The limestones have a gentle inclination to the south-west (see Section, 

 p. 29); their lower beds successively disappear as we go down the river, under 

 the outcropping edges of the upper layers. Right and left of the Vezere these 

 calcareous strata stretch far away, with a N.W.-S.E. 'strike,' through the 

 Departments de la Dordogne and du Lot on the one hand, and through the 

 Departments de la Dordogne, de la Charente, de la Charente Inferieure, &c., 

 on the other (see Map, p. 29). 



These limestones (k in the Map and Section) mostly belong to the Cretaceous J 

 System, that is, all those forming the thirty miles of country from below La 

 Linde, along the Dordogne and the Vezere, to about three miles north-east of 

 Montignac (near Aubas). There Jurassic limestones and Infra-lias (i, h,f) form 

 the ground for about three miles ; and above this the Vezere has its course through 



* The Geology of the Department de la Dordogne has been treated of : in MM. Dufrenoy and Elie de Beau- 

 mont's ' Explication de la Carte Geologique de la France ; ' in M. le Vicomte d'Archiac's ' Histoire des Progres 

 de la Geologic,' &c., in which are given references to previous writings on the subject ; and in several memoirs 

 by Coquand, d'Archiac, Hebert, Arnaud, Harle, and others, in the ' Bulletin de la Societe Geologique de 

 France.' A notice of the Dordogne Chalk and Fossils also occurs in M. d'Archiac's ' Geologie et Paleontologie ' 

 (8vo, Paris, 1866), p. 605, &c. The accompanying sketch-map has been taken from Dufrenoy and Elie de 

 Beaumont's Geological Map of France. 



f The Orleans Railway passes near Condat ; and from the Railway-station there, under the guidance of 

 the late Henry Christy, many of his friends have started, after examining the Badegoule Cave, on pleasant 

 trips down the Vezere, by taking boat on its little tributary the Ser (" Cerne " in some maps), near Condat. 



J M. d'Archiac says that the zone of Cretaceous strata on the south-west of the Central Plateau extends 

 from Souillac and Cahors (Dep. du Lot) to the Island of Oleron, with a length of 70 leagues and a breadth 

 of 15 leagues. 



E 2 



