Prof, Eiickland on the Structure of the A Ips, [J u N B, 



already described. It is composed exclusively of tertiary 

 strata ; i. e. magelflue, molasse, and freshwater formations. 

 These probably rest (on their NW side at least) on the prolon- 

 gation of the upper beds of the Jura Chain dipping towards the 

 Alps.. , 

 ; .. 1.' .^ . 2. Valley of the Danube. 



The same Tertiary formations extend on from Switzerland 

 into the Valley of the Danube, along which they continue east- 

 ward, with two partial interruptions near Vienna, into the great 

 plains of Hungary and Transylvania. 



The south frontier of this Valley from Switzerland to Vienna 

 IS formed by the Alps. Its north border, by the continuation of 

 the Jura into the Rouh Alp, and afterwards by the granitic rocks 

 'which are connected with the great primitive mass of the south 

 of Bohemia, and run in a hue nearly parallel to the Danube 

 from.Ratisbon to Lintz and Melk, It is probable that the fun- 

 damental rocks of this great valley are transition and primitive, 

 ■since the latter are seen emerging from beneath the tertiary 

 formations along great part of their north frontier. While on 

 their south border from Saltzburg nearly to Vienna, they repose 

 immediately on transition rocks. 



3. Valley of the Po, 



The central portions of the Valley of the Po are so completely 

 covered by gravel, that we can only form conjectures as to the 

 rocks that he immediately beneath it. But as the first strata 

 that appear on the edges of this gravel are referrible to tertiary 

 formations, it is probable that their prolongations stretch across 

 from the base of the Alps to that of the Apennines. 



Their position and character in the Subapennine Hills has 

 been well described by M. Brocchi ; they may be seen to great 

 advantage on the south of Parma and Placentia resting on the 

 transition limestone, greywacke and serpentine of the Apennines. 



On the north flank, they are admirably displayed in the Subal- 

 pine Hills, near Verona and Vicenza. And at the western 

 extremity, they form considerable hills on the right bank of the 

 Po, immediately east of Turin : the hill of Superga, near Turin, 

 is a remarkable point on this formation. 



J'he following Tabular Arrangement of the Rocks that occur in the 

 Continental Districts mider Comideration, with their Equiva^ 



: lents in England, may assist to establish an Understanding 

 between the Ueologists of the Two Countries. - 



ENGLISH FORMATIONS. FORMATIONS OF THE CON- 



TINENT. 

 Alluvium. Alluvium. 



Effect of causes now in action. Effect of causes now in action. 



Mud of rivers, deltas, grarel of torrents. Sanie as in England, but oa a larger 



scale. 



