XL] 



GRANITES AND GRANITIC VEIN-STONES. 



219 



tion to the great dikes of granular limestones found traversing 

 gneiss near Auerbach in the Bergstrasse, which Bischof has 

 described as true vein-stones. These endogenous concretionary 

 limestones are in fact to stratified limestones what endogenous 

 granitic veins are to gneiss rocks. 



