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Perna, two species, Ostrsea, Corallines, &c. In mineral characters 

 these beds, it is said, closely resemble some of those of Whitby, 

 from which, together with the complexion of the fossils, and their 

 place in the series, the author refers the group to the lias. An 

 overlying red, encrinite limestone, contains at least five or six species 

 of Ammonites and some Belemnites; amongst the former is the 

 A. multicostatus. This red limestone crops out on both sides of 

 the valley of the Salza near Hallein, and reappears in various places 

 in the Salzburg Alps (Aussee, Ebensee, &c). 



6. Salt Deposits. — The place assigned to most of the salt-mines of 

 the Austrian Alps in the memoir of last year, has been confirmed ; 

 and additional sections are given at Halstadt and Aussee to prove 

 that the salt masses in these places are fairly encased in Alpine lime- 

 stone. In other localities, however, as above indicated, this mine- 

 ral is shown to occur in the same formations as in England. 



7. Upper Alpine Limestone, or Upper Oolite. — In this group the 

 author comprehends semi-crystalline, brecciated, scaly, compact 

 and dolomitic limestones. The Hippurite limestone, though with 

 some doubt, is considered to mark the superior limit of the series, 

 the author having been led to this conclusion from the relations 

 seen on the north flank of the Untersberg, at Windischgarsten,Gosau 

 and the Wand, in all of which places there are passages from the 

 Alpine limestone into the Hippurite rock. 



8. Sandstone, Calcareous Grit and Shales, Slaty Limestone, fyc— 

 The Gres de Vienne is placed by the author as the lowest member 

 of this group ; although in the eastern termination of the Alps he 

 agrees with M. Boue, that its separation from the Alpine limestone 

 cannot well be effected. All along the chain, however, from the Enns 

 to the lake of Constance, he thinks that the grits and shales with 

 fucoids constitute a natural group distinguished in external charac- 

 ters from the Alpine limestone, and that they there form the lowest 

 term of the green sand. He then describes several transverse, pa- 

 rallel sections across that zone. The first of these is in the valley of 

 the Allgau or Sonthofen, in the upper end of which, near Miesel- 

 stein, the grits and fucoid shales are broken through by gneiss, 

 which appears to have been heaved up in a solid form posterior to 

 the deposition of the former ; whilst in an adjoining gorge dikes 

 of igneous rocks seem to have made unavailing efforts to pierce 

 through the overlying mountain of the Schwarzenberg. The dis- 

 locations and inversions of dip in the parallel ridges of the Allgau 

 are described in detailed sections. At the mouth of the valley, the 

 Grinten, a narrow serrated mountain, ranging E.N.E. and W.N.W., 

 is composed of many of the same rocks described last year at Nes- 

 selwang, but owing to a complete reversal of dip the lowest beds 

 or inferior green sand are thrown into juxtaposition with a ridge 

 of conglomerate of tertiary age, which dips to the north beneath 

 the molasse of the plain. The lowest beds are nearly vertical, and 

 consist of brown chert ; these are succeeded by green, calcareous 

 sandstone and grit highly inclined, containing Inoceramns concentric 



