134 NERBUDDA DISTRICT. 



from the vertical was observed, forming a dip of about 70° to 80° to the 



north. Now on examination it appeared that this dip was constant all 



round the granite mass and noticeably on the south of it. 



Again, with reference to the mineral alteration of the schists, a similar 



- . , „ independence of the granite vicinity has been al- 



Prevalence of gneiss- x ° * 



ose character coincides reac U stated to exist, notwithstanding which, it 

 with prevalence of gra- J ° 



ni te - is certain that, in the strip of the crystalline rocks 



included in the south portion of our map, much more granite is seen 



than elsewhere among these rocks, and that at the same time the whole 



series, as there found, is much more gneissose in general character, more 



hio-hly crystalline, and more thoroughly metamorphosed in aspect. 



Considered lithologically, the schists present many varieties, but even 



-. ± , , n f , a cursory description of these would be tedious. 



Lithology of the J r 



schists. They are however capable of being roughly group- 



ed under a few classes, and it may be convenient to mention, and briefly 

 describe the principal of these. We shall then speak of — 

 the Calcareous group, 

 the Argillaceous group, 

 and the Arenaceous and Siliceous group, 

 premising that the classification is very arbitrary and quite irrespective 

 of relative age. 



That sub-division of the metamorphic rocks of the Nerbudda district 



which is characterized by the presence of carbon- 

 The calcareous schists. 



ate of lime is undoubtedly the most prominent 



and remarkable portion of the series, and if the whole of the beds so 

 characterized be considered, the aggregate thickness must be very great 

 in some places : but among these calcareous schists there occurs an 

 endless variety of gradations, the typical farm of the group being the sac- 

 charine limestones, which may be considered as shaded off into sometimes 

 the arenaceous, and sometimes the argillaceous schists. The saccharine 

 limestone shows, save onlv in a few of its massive beds, a more or less 



