PHYLLITE SERIES. 113 



knolls, mounds and ridgelets, seldom more than 200 feet above the 

 nearest alluvium and frequently much mixed up with the latter. The 

 1 inch = l mile topographical maps show very distinctly by the highly 

 complex and sinuous windings of the contour lines, the change from 

 the one formation to the other. On the other hand it never, or very 

 seldom, sinks to such low-level peneplains as has been the case 

 with certain of the Aravalli rock complexes. It is essentially 

 the home of the Bhil people, who invariably build their scattered 

 and frail wattle dwellings dotted about in completely detached 

 huts and homesteads in lieu of collecting together into large villages 

 or towns. A so-called village as marked on the map. covering, it 

 may be. several square miles, is simply a loose assemblage of single 

 huts in each of which one family resides. 



As the name " Phyllite "" implies, the chief member of the series 



,..,,,. .. is a markedly thin-bedded rock of slightly 

 A thm-bedded argu- J . 



lacoous aeries with metamorphosed argillaceous type, but it 

 white quartz veins. ^ freely interbedded with more arenaceous 



quartzitic strata though these never attain to the importance 

 and pure simplicity of the characteristic massive Delhi Quartzite. 

 The colours are generally pale or dark sombre tints of grey, 

 khaki, yellowish, purple and green, and these are everywhere, 

 so far as exposed in Idar, freely interspersed with the white 

 tints of ramifying quartz veins. These latter are as typical as 

 the phyllites themselves, inasmuch as many of the small mounds 

 and ridges owe their preservation as elevations to a backbone of 

 these quartz veins. 



Minute mica scales sheathe the surfaces of all the finely divided 

 layers of the rock which is also generally contorted or minutely 

 wrinkled. Magnetite is fairly common in rather large crystalline grains 

 in some varieties, as for instance 4 ? 5 9 6 (12443, PI. 13, fig. 6) from £ mile 

 south-west of Mori. Some of the scattered examples from the 

 neighbourhood of Thuravas and Tembana Math are a trifle more 

 mineralised, biotite being associated with the sericite and also some 

 tourmaline, as in specimen ^V Chlorite and magnetite-schists are 

 seen feebly at Tembana Math and at Janali. There appears to 

 be some slight discordance between the strike of the Tembana 

 Math-Modhri outcrop, which runs N.E. — S.W. and the winding 

 outcrop of the Delhi Quartzite ridge lying to the south and east. 

 The surface alluvium, however, hides so much in this little bay 

 among the Delhi Quartzite ridges that one can say nothing certain 



