Structure of the Eastern Alps. 331 



bouring- iron furnaces. So far, the strata of the Griinten offer striking- analogies 

 to certain, well-known formations of the age of the green-sand, and probably 

 also of the chalk; but in the gorge by which the Starzlach flows into the Iller, we 

 meet with a series of beds entirely unlike any of the British, secondary groups. 



Prom the repeated changes of dip on the south side of the Grihiten, it 

 becomes extremely difficult to determine the exact order of the strata. But 

 the scagiia (or red chalk ? ) and the marly limestone (or planer kalk ? ) are 

 thrown off towards the west from the Hohe Wand, and are seen no more 

 between that peak and the Starzlach. The rocks between the highest ridge 

 and the river gorge, being in a nearly vertical position and in different degrees 

 of induration, have weathered into sharp ridges of rugged pinnacles, fol- 

 lowing the range and flexures of the several beds from the degradation of 

 which, they have derived their form. The most northern of these extraordi- 

 nary ridges, is made up of a coarse, brown, gritty limestone, passing into slatv 

 beds of calcareous, indurated marl, in which are obscure traces ofTerebratuke. 

 The next is composed of a bluish limestone with white veins, weathering to a 

 brownish red colour : it contains innumerable Nummulites, some fragments 

 of shells, and a few specimens of Spatangi. The third ridge occupies the 

 precipices on the banks of the Starzlach, and consists of indurated, dark co- 

 loured, calcareous shale, separated by stone bands of blue grit with white veins. 

 Subordinate to these calcareous shales are vast masses of irregularly bedded, 

 arenaceous iron ore, filled with a profusion of casts of shells, Crustacea, Echini, 

 &c. So convulsed are the strata containing the iron-stone, that the mineral, in 

 one mine, is reached by horizontal galleries from the sides of the ravine, the 

 ore being extracted from tortuous and nearly vertical beds with a slight incli- 

 nation to the south ; in a second, it is worked by shafts, the mineral beds 

 plunging to the north under a mass of calcareous, slaty shale ; in a third mine, 

 the same beds are snapped off at right angles to the preceding, and though 

 accompanied by numerous contortions, are on the whole nearly horizontal. 



On the great scale, the calcareous shale and grit containing the ore, may 

 be considered subordinate to the system of nummulitic limestone, which to 

 the north separates the iron mines from the Griinten ; and to the south of the 

 Starzlach rises into another parallel mountain chain, called the Mos, in which 

 iron ore is also partially worked. This limestone appears to contain three 

 species of Nummulites hitherto unpublished — one of them somewhat resem- 

 bling N. elegans is found also in the nummulitic beds immediately overlying 

 the green-sand and cretaceous system of the Untersberg* ; a second species 



* See Plate XXXVI. fig. 9. 



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