1848.] MURCHISON ON THE STRUCTURE OF THE ALPS. 283 



coralline, cavernous limestone with Pectens, Volutes, Olivse, Dentalia, 

 a large Fusus, Terebellum, &c. ; a third contains Balani and Tur- 

 binolise. Now, the white limestone associated with this group is 

 lithologically a true " calcaire grossier " loaded with nummulites. 

 Among these nummulites, whatever may be their names, M. d'Ar- 

 chiac, who has examined them at my request, has declared that the 

 four species to which he assigns them, all exist in the Lower Pyrenees. 

 One of these, the N. Icevigata, Lamk,, occurs also in the London 

 clay at Bracklesham, in the lower tertiary of Belgium, and in the 

 Yicentine ; and another is the form so very common in the Alps, 

 whether it be termed N. planospira (Boub.) or N. assilinoides 

 (Riit.) ; whilst a fourth is the N. granulosa (D'Arch.) of Dax 

 and the Pyrenees. These coincidences leave no doubt in my mind 

 as to the age of the beds. I may also add, that in no one of the nu- 

 merous rock-specimens I examined, is there an example of a nummu- 

 lite occurring in the same fragment as the hippurites ; and in fact there 

 is also a clear lithological distinction between the hard, compact and 

 flinty, white hippurite limestone, and the equally white but coarse 

 granular limestone with nummulites. 



The collections of Monte Gargano present, indeed, other fossils of a 

 much younger series in a calcareous tuff, and as among these are the 

 Pecten latissimus, Panopcea Faujasi, and other well-known sub- 

 apennine shells, the existence there of pliocene deposits, as along other 

 parts of the shores of the Mediterranean and Adriatic, is clearly 

 marked. 



On the Miocene, Pliocene, and Younger Tertiary Deposits of Italy. 



The existence of deposits of miocene and pliocene age in the north 

 of Italy has been long established ; but geologists have not sufficiently 

 directed attention to those sections in the peninsula, which best in- 

 dicate transitions from the one group to the other. In the first place, 

 therefore, I will endeavour to show, how in the north of Italy the 

 oldest miocene, if not partly eocene, gradually inosculates and passes 

 up into the overlying subapennine strata*. I have indeed already 

 to some extent illustrated this point in the sections of Bassano and 

 Asolo(p.223), and have said that M.de Zignowill soon have collected, 

 identified, and published the fossils which there lie in strata inter- 

 calated between the nummulitic eocene beneath and the subapen- 

 nine marls and conglomerates above them. 



The region to which I first invite attention, as exhibiting an unin- 

 terrupted succession from the top of the eocene or bottom of the 

 miocene, through a full development of the latter up into the most 

 copious accumulations of subapennine or pliocene, is that group of 

 hills called the Monferrato, which ranges itself in a horse-shoe form, 

 as defined by the course of the Po, between Turin on the west and 

 Alexandria on the east. In the great plain occupied by coarse drift 



* The reader who may desire to see the extent to which my observations and 

 conclusions agree witli those of other authors, may consult Pareto's Liguria Ma- 

 rittima, Pilla's Geologia, Philippi, &c. 



