Geology of the Harz Mountains. 211 



Zellerfeld, Grund, Wildemann, Lautenthal, Altenau, and St 

 Andreasberg; and on the Lower Harz, Elbingerode, Ben- 

 neckenstein, Ilfeld, Hasselfelde, Stolberg, and Harzgerode. 



The Kyffhauser is an isolated hill situated a few miles 

 from the southern edge of the Harz, close to the village of 

 Kelbra, which, but for its geological interest, would not have 

 been alluded to here. 



III. GEOGNOSY OF THE HAKZ. 



1. Archaean Eocks of the Kyffhauser. 



The red Permian sandstones and conglomerates of the 

 Kyffhauser rest on a basement of gneiss, a small patch 

 of which is seen peeping out along the N. side of the range 

 to the S.E. of Kelbra. The gneiss is highly crystalline 

 and sometimes granitic, and strikes in an approximately E. 

 and W. direction. It is associated with a beautiful highly 

 hornblendic diorite and a variety of very hornblendic syenite, 

 containing much sphene. The numerous granite veins by 

 which it is intersected are probably connected with a main 

 mass beneath, part of which is exposed on the face of the hill 

 immediately below the Kyffhauser tower. The geological 

 structure of this eminence is shown on section No. 2. The age 

 of the gneiss cannot be definitely fixed, as the requisite data 

 are awanting, but in petrographical character it most nearly 

 resembles the Archaean gneiss of other countries, and is 

 meanwhile relegated to that formation. 



2. " Kerngebirge," or older Palaeozoic Core of the Harz. 

 a. Hercynian. 



The oldest rocks of the Harz were formerly classified at 

 Upper Silurian, as they contain graptolites and other Silurian 

 forms. More recent researches, however, have led to their 

 being placed under a separate group, occupying a position 

 intermediate between Silurian and Devonian. This group is 

 named from the Harz " Hercynian," and corresponds to Bar- 

 rande's ^Stages, F, G, H, of the Bohemian basin. 



