14 FOOTE : GEOLOGY OF MADURA AND TINNEVELLY DISTRICTS, 



left or north bank of the Vaigai and is traceable for several miles 

 further to the east-north-east up to the great rocks west-south-west of 

 Trivadur where the central beds of the group have assumed a very- 

 granitoid appearance and contain much felspar. Whether the granular 

 quartz formation dies out here or is merely hidden by superficial deposits 

 and re-appears further to the eastward in the great granular quartz ridge 

 of Vallamalai (Vullamalay, sheet 80j or whether the latter represents 

 the lower granular quartz group (No. 2) are questions yet to be decided. 

 If the latter view is the correct one, then the picturesque rocky Tirumalai 

 (Sacred hill), 6 miles east-north-east of Vallamalai, and the Kunatur 

 (Coonatoor) Trigonometrical Station hill, 10 miles west-south-west of 

 Vallamalai hill station, represent the Sikandar Malai granite gneiss band. 

 5. The upper granitoid gneiss group occupies the plain north-west- 

 „,.. ward of the Trivadur Trigonometrical Station 



The upper granite => 



gneiss, or Melur group. ridge and stretches away south-westward down to 

 the alluvium of the Vagai and north-eastward under the alluvium of the 

 Palar and its tributaries, beyond which it re-appears and extends north- 

 eastward past Tirumayam (Tirmium) to beyond the confines of the map 

 illustrating this memoir. 



The special features of the granitoid rocks are very strikingly illus- 



, . ,. c „„„ trated in many of the hills rising out of this area 

 Characteristics or see- J ° 



nery. which show great beauty of form and colour in 



the noble rock masses they consist of. 



Two of the most striking views of this area were got from its nearly 

 opposite extremities. The one is from the southern 

 slope of the western part of Pramalai (itself re- 

 markable for a splendid scarp, facing south), as you look south-south- 

 westward across the rich and varied palm groves of the Palar valley 

 which form an exquisite foreground to the scene. The mid distance is 

 occupied by a well-wooded country out of which rise a very considerable 

 number of beautiful rocky hills, several of them surmounted by enormous 

 tors, the back ground being formed by the many picturesque peaks of 

 the o-reat Varshanad spur of the Southern Ghats. The western side of 

 \ 14 ) 



