286 Sir R. I. Murchison's Notes on the Alps and Apennines. 



have a wide range, extending into Moravia, and, doubtless, 

 constitute a large portion of what has been termed Carpa- 

 thian grit. But the author observes, that, in tracts like this, 

 where the cretaceous system assumes an arenaceous and 

 earthy form, and particularly in those districts where the num- 

 mulitic limestones no longer exist, it is exceedingly difficult 

 to draw any clearly-defined line of separation between sand- 

 stones of secondary and tertiary age. He, therefore, believes 

 that under the name of " Gres des Carpathes," rocks both of 

 eocene and cretaceous age have hitherto been confounded \ 

 and that arguments concerning the age of any given portion 

 of these sandstones in a country so constituted and so full of 

 dislocations, are valueless without the test of organic re- 

 mains. 



The Apennines. — A general view of the structure of Italy 

 is then offered ; and, whilst, on the authority of General della 

 Marmora, the existence of Silurian rocks in Sardinia is cited, 

 it is shewn that the lowest fossiliferous deposits of the Penin- 

 sula are liasso-jurassic, followed by limestones, often of red 

 colours, of Oxfordian age {ammonitico-rosso). These consti- 

 tute a number of parallel ridges of various altitudes, over- 

 laid by or forming troughs with younger accumulations, and 

 thus constituting numerous backbones, of which the Apuan 

 Alps and their crystalline marbles, the hills of La Spezia and 

 Pisa, are the most prominent examples in the North. 



Admirably exposed on the flanks of the Venetian Alps, and 

 scarcely less so at Nice, the cretaceous system, in all its 

 members (from the Neocomian limestones of foreign geolo- 

 gists or equivalents of the English lowest greensand, up to 

 the white chalk inclusive), is surmounted by nummulitic 

 eocene deposits, which, near Asolo and Bassano, are followed 

 by miocene and pliocene shelly strata. After shewing how 

 they occupy a trough between such Alps and the Euganaeans, 

 the author explains how the latter hills have recently been 

 described by M. de Zigno as composed of Oxfordian Jura and 

 a full cretaceous system up to the white chalk inclusive, 

 overlaid by the nummulitic group. In Liguria, Modena, 

 Lucca, and Tuscany, such clear evidences do not exist ; for 

 there the formations above the Oxfordian Jura are singularly 



