GNEISSIC EOCKS. 23 



limestone are seen along the high road in ditches and water-courses in 



the shape of large quantities of debris. The limestone is of extremely 



coarse grain and highly spathose in appearance. The limestone is of 



white colour. The country is, as already mentioned, very thickly covered 



with cotton soil, and I did not, during the cursory examination which 



alone T was able to bestow upon that particular tract, happen to light 



upon any outcrop of this rock in this neighbourhood. 



A few important outcrops of granite gneiss were observed further 



south in the valleys of the Virudupatti river and 

 Kolarpatti outcrop. 



of the Vaippar, notably a considerable group or 



low rocky masses on the left bank of the former river a little below 

 its junction with the Korai-Ar and opposite to the village of Kolarpatti 

 (Colaurputty). Another considerable outcrop of banded granite gneiss 

 occurs at the junction of the Virudupatti river with the Vaippar. Con- 

 siderable exposures of typical granite gneiss, all more or less approxi- 

 mating in colour to the typical Cope Coraorin gneiss, may be seen 

 in the bed of the Vaippar at Kolapatti 2 miles east of Satur. Another 

 noteworthy outcrop of similar highly garnetiferous banded granite 



gneiss occurs in the Waddakarai (Wudducurra) 

 Waddakarai bill. 



hill 4 miles south of that town and close to the 



South Indian Railway. The hill is a bare rock which is rapidly being 

 quarried away for railway purposes. The lamination or bedding which 

 is beautifully distinct strikes east-north-east to west-south-west (a very 

 prevalent strike in these regions), while the dip measures 60° — 65° 

 north-north-west. The hill which was formerly a station of the Trigono- 

 metrical Survey rises very abruptly out of a vast plain of cotton soil. 

 On the left side of the Vaippar valley the same wide spreads of 

 Outcrops east of the cotton soil prevail and allow of but very few out- 

 . Vaippar. crops being seen. The most interesting of those 



noted was a bed of very handsome pink and pinkish-white crystalline 

 limestone seen to the east of Shenkotai (Shencotta) 6 miles south of the 



great Pantalagudi limestone bed. The Shenkotai 



Sheukotal limestones. ^ c 



bed is exposed in the easterly ott-tiow channel ot 



( 23 ) 



