FOLDS AXD FAULTING. 405 



whether stratigraphical or tectonic, are reversed, the prin- 

 cipal massifs forming a curve, presenting their convex 

 front towards the south. On this hypothesis, therefore, 

 mountain ranges result from unequal contraction, and 

 are not the products of forces acting equally in opposite 

 directions. 



But further, the contracting mass is affected by hin- 

 drances, and re-acts upon these in a peculiar and striking 

 manner. After overlapping the old gneiss of the Dole area 

 and the ancient continental regions of the Black Forest and 

 Bohemia, the younger Alpine series, freed from the resist- 

 ance of these higher districts, spread over the lower grounds 

 of Galicia, unconformably overlying the older carboniferous 

 beds of that province ; Professor Suess, indeed, considers 

 that the north-east and south-west foldings, which can be 

 traced through the Erzgebirge, along the Rhine into Bel- 

 gium, and over to our own islands, are the result of the 

 action of that powerful pressure which the outstanding 

 sentinels had only apparently successfully resisted. 



The discussion as to the transgression of the Cenoma- 

 nian, both in Europe and Asia, has proved that these earth 

 folds have not been mere local phenomena, but that we are 

 dealing with events of the highest importance in physical 

 geology. It has now been shown that the Upper Creta- 

 ceous beds transgress over the older in Northern Europe, 

 Northern Africa, India, and Eastern Asia, and we have 

 also lately learnt that the same holds good for Chili. 



At the recent Swiss Congress Professor Steinmann gave 

 an account of the fauna of the Ouiriquina beds in that coun- 

 try, and showed that three-quarters of the Ammonites there 

 met with are absolutely identical with Indian types, the 

 Gasteropoda and Lamellibranchiata being also similar to 

 those occurring in the Utatur strata, near Pondicherry, and 

 therefore he deduces that, like these, the Chilian beds must 

 be of Cenomanian age. The similarity extends yet further, 

 the transgression being as strongly marked in these strata 

 as in the Indian type. 



The Shore Cordilleras consist of mica schists, granites, 

 etc., and these older rocks are directly overlaid by the Quiri- 



