26 CRETACEOUS ROCKS OF S. INDIA. [PaRT T. 



grits, of which these Hills are composed, and capping the higher parts of 

 the roUing ground beyond. The country to the North-west of this, and 

 comprising the great portion of 'the Pondicherry area, is occupied by the 

 older group, for the most part unfossiliferous, but containing one fossi- 

 liferous band just where it is overlapped by the Arrialoor group; and 

 hence were derived the fossils of Messrs. Kaye and Cunliffe's collec- 

 tions. That these latter beds are not equivalent to any portion of 

 the Trichinopoly marine series, but are of older date, is a point 

 upon which little doubt can be entertained. It is certain indeed 

 that, as above remarked, some species of Cephalopoda are com- 

 mon to the two sets of beds, but not only do these species form 

 a very small percentage of the total number in each fauna, but they 

 are among the least abundant species in each case, while the Geological 

 affinities of the two faunas, taken in the mass, tend in opposite directions : 

 that of the Ootatoor group recalling rather the Gault and Upper 

 greensand forms, while, as remarked by Professor Forbes, that of the 

 Pondicherry beds is decidedly Neocomian, In order to avoid miscon- 

 ception, it will perhaps be best to speak of the Pondicherry beds under 

 a distinct name, which implies no pre-judgment of the question of their 

 age. The ' Valudayur' beds will be convenient for this purpose, the name 

 being taken from the village* near which is the fossiliferous locality 

 alluded to. 



In the detailed description of the Cretaceous rocks, to which the follow- 

 ing pages are principally devoted, I shall follow a similar course to that 

 adopted in this introductory chapter ; commencing with the Trichinopoly 

 district, which is not only the most extensive, but also that in which the 

 different formations are best displayed, and their mutual relations most 



* I write this name as it is pronounced by the Natives and by the French, and as it is 

 marked on the Map. The English corruption, Vcrdoor, is quite unintelligible to the Natives, 

 as I found during my first day's experience of the country, my servants, tents, and baggage 

 going astray in consequence, and leaving me to the hospitalities of a dismantled bungalow. 



