408 STRATIGRAPHICAL GEOLOGY 



massive limestones of which the thickness often amounts to several 

 thousand feet. They indicate, in fact, a continuance of the pelagic 

 conditions which prevailed in the same region during Triassic 

 times. 



In the Western Alps Haug has described the Lias as forming 

 three distinct bands round the core of the Cottian Alps ; the 

 innermost consisting of crystalline limestones, often brecciated and 

 containing large blocks of the older rocks, but frequently fossili- 

 ferous and characterised by a fauna of Corals, Lamellibranchs, and 

 Gastropoda ; the second formed of compact limestones (never 

 crystalline), characterised by the abundance of Ammonites ; and 

 thirdly, bedded limestones with Crinoids and many Brachiopoda. 

 He regards these three facies as replacive, one outside the other, 

 probably formed in zones of increasing depth of water. 



The outer belt is well developed round Digne and in the 

 Basses Alpes, where all the French divisions can be recognised, and 

 the several thicknesses are as below given : 



Feet. 

 Toarcian (bifrons and radians zones) .... 660 



Charmouthian (limestones and marls) .... 860 



Sinemurian limestones ....... 200 



Hettangian (180) and Rhaetian (120) . . . .300 



2020 



In the Tyrol and Eastern Alps the Lias is represented by red and 

 variegated limestones and spotted marls (Fleckenmergel), all of which 

 abound in Cephalopoda. The Rhsetic zone of Pteria contorta here 

 forms a link between the Trias and the Lias, being in some 

 localities a part of the great Dachstein limestone, but the typical 

 Kossen Beds are marls containing P. contorta and black limestones 

 with many Brachiopoda. In the Adneth and Salzburg district 

 the highest member of the Rhaetic is a limestone full of the coral 

 Calamophyllia ( = Lithodendrori), and this is overlain by variegated 

 limestones containing many Ammonites of the genera Arietites, 

 Phylloceras, and Lytoceras which must represent the Hettangian and 

 Sinemurian stages. 



In the Bavarian Alps the Middle Lias is represented by varie- 

 gated marls with Amaltheus margaritatus, but elsewhere it does not 

 seem to be specially distinguishable in the mass of limestones 

 and marls. 



The Upper Lias (or Toarcian) is more clearly definable, its 

 equivalent in the Bavarian Alps being red and grey limestones 

 with Hildoceras bifrons, and in the Tatra district near Vienna by 

 fleckenmergel with the same fossil. 



Farther east the whole formation passes into a littoral facies of 





