22 GEOLOGICAL MEMOIRS. 



CEiiingen deposits (superposed on the Upper Freshwater Molasse) 

 as belonging to the Miocene period. It results then that the greatest 

 disturbance affecting the Swiss and Vorarlberg region has taken 

 place between the Miocene and the Drift periods. 



M. Escher adds a Supplement relative to his researches on the 

 Trias in Northern Lombardy ; and supplies detailed sections of 

 several localities on the borders of Lake Como, in the Val Brem- 

 bana, Val Trompia, &c. 



M. Heer's description of Plants and Insects of the Trias and Lias, 

 illustrative of M. Escher' s researches, follows. 



The work is furnished with valuable Tables of the fossils of the 

 Lias, — of the geological formations in the Vorarlberg and in Lom- 

 bardy, showing the collated observations of Emmerich, Schafhautl, 

 von Hauer, Escher, &c., — of the distribution of the fossils in the 

 St. Cassian beds of different localities, &c. ; and it is illustrated with 

 eight 4to Lithograph Plates of the fossils of the Lias, the St. Cassian 

 beds, Muschelkalk, Keuper, and Bunter-Sandstone, and with two 

 large plates of Sections, besides several woodcut diagrams in the text. 



[T. R. J.] 



On the Cephalopoda of the Hallstatt beds. 

 By F. R. von Hauer. 



[Proceedings of the Imperial Academy of Sciences of Vienna, Dec. 7, 1854.] 



M. von Hauer described 17 new species of Cephalopoda, viz. 14 

 Ammonites, 2 Nautili, and 1 Orthoceras. These were for the most 

 part discovered by Dr. Fischer, of Munich, in the environs of Aussee 

 in Northern Styria ; and increase the number of Ammonites pre- 

 viously known as belonging to these strata by nearly one-half. 



None of the species at present known beyond the Alpine Range 

 are found amongst the numerous specimens collected by Dr. Fischer ; 

 nor is this surprising, since the results of recent investigations 

 entitle us to consider the Hallstatt beds to be an upper Triassic 

 deposit, wanting beyond the Alps, — or perhaps represented else- 

 where by the Keuper, which is so poor in marine fossils, and espe- 

 cially destitute (as far as our present information goes) of Cepha- 

 lopods. 



The features of this Cephalopod-fauna of the Hallstatt beds corre- 

 spond exactly with the geological position assigned to them. It 

 forms a connecting link between the faunas of the Secondary and 

 Palaeozoic periods, including genera known to belong to the most 

 ancient deposits, as for instance, Orthoceras, completely evolute 

 Nautili, and Ammonites with smooth lobes and saddles, together 

 with Ammonites of the arietes, heterophylli, and ceratitce families, 

 exhibiting an evidently Jurassic type. 



The Hallstatt beds have also afforded two Corals (described by 

 Prof. Reuse, in connexion with M. von Hauer' s memoir) ; one of 

 them belonging to the genus Isastrcea ; the other being a Fletcheria, 

 a genus which has been thought until now to be peculiar to the Si- 

 lurian strata. [Count Marschall.] 



