THE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[THIRD SERIES.] 



APRIL 1845. 



XXXIX. On the True Geological Position of the Macigno 

 Formation in Italy and in the Soiith of Europe. By Prof. 

 Leopold Pilla*. 



A MONO the formations which are the most extended in 

 -^* _ Italy, the macigno occupies a remarkable place. A 

 great portion of the heights of Tuscany and of Liguria is com- 

 posed of this formation, which extends also, on one side into 

 the maritime Alps and those of Lombardy ; on the other, into 

 the kingdom of Naples and as far as Sicily. On leaving Italy 

 we meet it with the same characters in the Pyrenees, on the 

 northern sides of the Alps, in Greece, in Turkey, and, in ge- 

 neral, in all the southern portion of Europe. It appears to 

 mark the principal line of division between the geological zone 

 of the north and the south of Europe, — a hne which, as re- 

 gards the formations under consideration, does not appear to 

 extend on the west beyond Provence and the pi'ovince of 

 Nice; on the east, the Carpathian Mountains. At the com- 

 mencement of this century, and during the prevalence of the 

 Wernerian theories, false ideas were entertained respecting 

 the age of this formation, which was generally considered as 

 belonging to the graywackef. But it was soon seen that it oc- 

 cupied in Italy a place between the Jurassic and the tertiary 

 formations ; and from that time the necessity was seen of 

 carrying its age up to the chalk. This idea has been more 

 and more confirmed, and at present it is adopted by all geolo- 

 gists, only that very little attention has been paid to fixing "mitli 

 precision the stage which the macigno occupies in the creta- 

 ceous group. But a particular study of this deposit, a more 

 thorough examination of its geological relations, of the fossils 

 which characterize it, and of many accidental circumstances 



* From the Comptcs liendus de fAcnd. des Sciences, January 1845. 

 f Brocchi, ConcJnologia Fossile Svbapennbia. 

 Phil. Mag, S. 3. Vol. 26. No. 173. April 1845. U 



