GRANITOID AREAS. 39 



low rocky hill 6| miles further to the east-by-north. Enemerla hill is 

 formed of bare black rocks rising to a height of from 300 to 400 feet 

 above the surrounding plain. The quartzo-hornblendic rock is coarsely 

 crystalline in texture, and towards the western end of the mass rather 

 porphyritic ; no bedding is seen, and its relations to the surrounding 

 schistose gneiss is not clear, no contact of the two rocks being exposed. 

 The Enemerla rock is not more trappoid than beds of crystalline horn- 

 blende rock unquestionably forming part of the gneissic series, and but 

 for its position miles away from similar extra-metamorphosed rocks, I 

 should not have any hesitation in regarding it as such a rock ; but, as it is, 

 I feel doubtful whether it may not be intrusive and trappean. 1 The 

 same remark applies to the smaller trappoid mass south-west of 



Ianakotay (Ianacota), but in lesser degree, as it is 

 Ianakotay hill. 



unquestionably associated with a set of highly 



hornblendic gneiss beds underlying the rather remarkable Ayawarpalle- 



Ianakotay quartzite band. The hill consists of great masses of rock, much 



weathered, rounded, but not sufficiently isolated and detached to be called 



tors. The hill is almost bare of vegetation, and of inky blackness. 



It is not possible to examine the geological map of the Guntur-Ongole 



region without being struck by the remarkable 

 Parallelism of folding 

 of gneiss and Kadapa parallelism subsisting between the great foldings 



' of the gneissic rocks and those of the Kadapa 



rocks in the Yellakondas and Nallamallas. The natural inference from 

 this is that the gneissic series was affected by at least two great periods of 

 (roughly speaking) east to west compression, and the Kadapa series by 

 one such period, which was the second of the two. That the gneissic 

 series had been compressed into huge folds at a period long anterior to 

 the commencement of the Kadapa, is abundantly clear from the fact 

 that such folds had undergone great denudation before the begin- 

 ning of the deposition of the newer series. On the completion of the 



1 My examination of Enemerla hill in 1866 was not as full as I could have wished, 

 owing to a very heavy hurst of the monsoon, which came up and drove me away. No 

 suhsequent opportunity occurred of my revisiting the locality. 



( 39 ) 



