Structure of the Eastern Alps. 391 



This coralline limestone, which is of such great thickness at Wiklon, is less 

 developed and less indurated at Ehrenhausen, where, after occupying- the 

 castle-hill on the right bank of the Mur, it passes under saponaceous marls 

 alternating with strong bands of brown, calcareous grit. These masses con- 

 stitute cliff's which are continually crumbling away in consequence of the 

 decomposing nature of the marls. 



4 a. White and blue marl with bands of sandstone, white raarlstone, and concretionary, whitt- 

 limestone, 



Beds of this kind, representing the upper portion of the coral limestone 

 series in its expansion towards the east, are well exposed in a succession of 

 escarpments on the right bank of the Mur below Ehrenhausen. In that part 

 of its course the river is bounded to the north by the great plain of Strass and 

 Mureck, and to the south by a succession of tertiary hills composed of strata 

 like those we have just enumerated. 



Descending from Ehrenhausen by the right bank of the river, we find the 

 coral limestone succeeded, and perhaps in part replaced, by light-coloured, 

 unctuous marl, with bands of micaceous calc-grit, which, near the bridge of 

 Strass, are superseded by blue, sandy marls. 



We obtain a good transverse section of the district to the south of the river 

 by deviating from the direct line of section, and following the great road to 

 Marburg. This road first conducts us through the hills of Santa Egida, where 

 beds of concretionary, white limestone alternate with marls containing fossils, 

 among which we observed a Scalaria, a Cypraea, Ostrea Bellovicina, an(! 

 many fragments of Pecten pleuronectes (?). Still further to the south in t[ie 

 Zirknitz-thal (from which the waters flow into the Drave at Marburg), many 

 fossils have been discovered along the line of a new road : from amongst these 

 we procured a Clypeaster (Echinanthus marginatus (?) of Leske); Pectens 

 of gigantic size, one of which is the Pecten figured by Faujas from Maes- 

 tricht; and Ostrea longirostra (Lamarck). 



To the west of the valley of Zirknitz, and consequently in the line of bear- 

 ing of the strata which succeed the coral limestone of Ehrenhausen, the system 

 of white marls, we are describing, assumes so compact a character, that at St. 

 Kunegund and some other places they are extensively quarried as a building 

 stone. This stone much resembles the compact beds of English clunch (or 

 indurated chalk marl), and is remarkable for its dark-coloured blotches, which 

 at a little distance resemble flints in chalk. It is sometimes finely laminated ; 

 but it is more frequently thick-bedded, with a dull, conchoidal fracture, and 

 has occasionally been employed in coarse statuary work*. 



* The gigantic figures at the mausoleum of the castle of Ehrenhausen are of this stoiio. 



