NEOZOIC GEOLOGY IN EUROPE. 479 



great bend of the Rhone above Geneva, Golliez (5) has 

 brought forward evidence of pre-Carboniferous folds. The 

 "cornes vertes " in the Dent du Mercies strike N.N.E. 

 to S.S.W., and the Carboniferous rocks rest upon their 

 upturned edges. 



Leaving the Alps we must notice here a second paper 

 by Bertrand (6) upon the various systems of folds through- 

 out France. He still maintains the two laws which he has 

 already attempted to prove; viz., (1) that when once a 

 system of folding is established, subsequent folds tend to 

 be formed along the same lines ; (2) that, in France at least, 

 in spite of various sinuosities, the lines of folding form an 

 orthogonal network. On the map which accompanies this 

 paper the most conspicuous of the two systems of folds has 

 a general east to west direction ; but the lines, instead of 

 being straight, are slightly curved, the concavity facing the 

 north. This concavity increases as we proceed from the 

 north to the south, and towards the Central Plateau it be- 

 comes double. The westerly concavity spreads down into 

 the department of Ariege ; the easterly again bifurcates, 

 extending on the one hand into the valley of the Po, and 

 on the other into Provence and the Alpes Maritimes. 

 The second system of folds lies nearly at right angles to the 

 first, but is very much less conspicuous. 



As to the mode of formation of folds, Ziircher (7) has 

 made some observations which are worthy of note. He 

 believes, no doubt correctly, that a fold is not formed along 

 its whole length at one time, but that it originates at one 

 point and gradually spreads in two opposite directions from 

 that point. And he concludes, on perhaps somewhat im- 

 perfect evidence, that the point where the folding is now 

 most intense is the point where it first began to be formed. 



Among papers dealing with special areas there is one 

 by Tardy (8) upon the faults and folds in the Jura, which 

 is, however, very brief and general in its statements. In 

 the Corbieres in Languedoc Grossouvre (9) has proved the 

 existence of a thrust plane which he traces from St. Louis 

 to Corbieres, and which lies on the north side of the anti- 

 clinal which bounds the Albian basin of St. Paul de 



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