Geological Society. 291 



various essays, published during the past year, on the structure of 

 the Alpine and Carpathian chains*. 



In elucidation of the geology of the Eastern Alps, a paper was also 

 presented to the Society, during the past year, by Mr. Murchison 

 and myself. Our object was, by help of a transverse section along 

 the line where we crossed the Chain, to bring together such facts 

 as were seen by ourselves, and appeared of any real importance : and, 

 connecting them with other facts, partly derived from oral informa- 

 tion, and partly from a number of scattered memoirs little known in 

 this country, to give such an outline of the general structure of 

 the whole chain, as should be intelligible to an English reader. 



As our Memoir has been published, I should hardly have alluded to 

 it, had not our views been partially misrepresented - } and, what is of 

 vastly more importance, had we not differed from Dr. Boud in the 

 interpretation of some very singular, and we think not unimportant, 

 phenomena. 



During the past year, Mr. Murchison again visited the same region; 

 and the results of his investigations have been laid before us in an 

 elaborate paper, which I am now called upon to notice, in doing 

 this I am compelled so far to retrace my own steps as to bring 

 to your recollection the geological subdivisions of the Alpine chain 

 adopted in our published Memoir. We stated that the Eastern Alps, 

 considered in their greatest simplicity, might be described as a mountain 

 chain with an axis of primary rocks, flanked and surmounted by two 

 great secondary calcareous zones, which are in their turn surmounted 

 by vast tertiary deposits, descending on one side into the plains of 

 Italy, and on the other into the plains of the upper Danube j and that 

 the same great physical region, when considered in more detail, might 

 be separated into formations admitting of a general comparison with 

 those of our own country in the following order, commencing with 

 the lowest. 1. Primary rocks of the central axis. 2. Highly crystal- 

 line deposits graduating in the ascending order into rocks conforming 

 to the ordinary transition type, and containing, though very rarely, 

 transition fossils. 3. Red and variegated sandstone and gypseous 

 marls, sometimes alternating with masses of magnesian limestone. 

 4. Older Alpine limestone a formation of enormous thickness, sup- 

 posed to represent a part of the oolitic series, and based upon fetid 

 dark-coloured limestone and other strata which we endeavoured to 

 identify with the lias. 5. Limestone and sandstone with great masses 

 of saliferous marls rolled up and encased among the contorted strata. 

 6. Younger Alpine limestone, including all the secondary deposits 

 of the Alps superior to the saliferous system, and containing two 

 distinct groups j the first of which was supposed to represent the 

 highest portion of our oolitic series, and the second (or Vienna sand- 

 stone) the whole system of the green-sand and chalk. 7. Tertiary 

 deposits. 



Between the two subordinate groups of No. 6. we were not able to 

 draw any precise line of separation j and, to our surprise, we were 



* See especially several elaborate articles on these subjects, published by 

 Dr. Bone, during the past year, in the Journal de Gfologie. 



2 P 2 still 



