Geological Society. 



still less able to define the limits of the secondary and tertiary series. 

 For, sometimes resting unconformably among the serrated peaks of 

 the higher mountains, and sometimes in a position intermediate be- 

 tween the outer zone of the chain and the tertiary plains descending 

 towards the Danube, we found great complex deposits, apparently 

 graduating at one extremity into the secondary, and at the other 

 into the tertiary system, and abounding in fossils, which in a great 

 majority of the species seemed to conform to the tertiary type. 

 Upon this mixed evidence we concluded that these singular deposits 

 formed a true connecting link between the secondary and tertiary 

 systems of the region; and, though unknown in our own country and 

 the North of France, were to be placed somewhere between the cal- 

 caiw grassier and the chalk. 



To the clearing up of this point (on which alone we had any essen- 

 tial disagreement with Dr. Boue), Mr. Murchison has devoted the 

 most elaborate details of his recent Memoir. He first describes the 

 extension of the primary axis into the Leitha-gebirge, which thus 

 seems to form a connecting link between the Alpine and Hungarian 

 chains, and notices some new and interesting localities of the mag- 

 nesian limestone and red marl series. He then traces the reappear- 

 ance of the gypseous and saliferous marls, apparently of the age of 

 the new red sandstone, in some longitudinal valleys of the Salzburg 

 Alps ; and by means of detailed sections, fixes the great salt deposits 

 of Aussee and Halstadt between the older Alpine limestone based 

 upon lias, and the newer limestone terminating in the Hippurite rock. 

 He afterwards gives various sections of the Vienna sandstone group, 

 and shows that it is the equivalent of the green-sand and chalk ; and 

 proves, by very elaborate details, chiefly derived from the banks of the 

 Traun, that in the enormous development of the nummulite series one 

 part graduates into the secondary, and another into the tertiary sy- 

 stem of the Eastern Alps ; thus confirming by new and uninterrupted 

 sections the justness of our former classification. 



Among the novel and important observations in this Memoir, the 

 author describes a deposit, at Ortenburg in the valley of the Danube, 

 composed of chalk with flints, supporting tertiary sands and clays, and 

 resting horizontally upon the primary rocks of the Bohemian chain. 

 Arguing from this fact he shows, (agreeably to the system of M. Elie 

 de Beaumont,) that the elevation of the Alpine and Bohemian chains 

 took place at two distinct periods. 



In glancing over the various papers on the structure of the Eastern 

 Alps, it was impossible for me entirely to separate the descriptions 

 of the older and newer systems ; but I now proceed to notice some 

 communications almost exclusively devoted to the phenomena of ter- 

 tiary deposits. 



A paper was laid before the Society by Mr. Murchison and myself, 

 during the past year, on the Tertiary Formations of Lower Styria. 

 In an east and west section, from the Styrian Alps to the confines of 

 Hungary, we describe along succession of marine strata; commencing, 

 as we have endeavoured to prove by the imbedded fossils, with rocks 



of 



