94 CRETACEOUS ROCKS OF S. INDIA. [PART II. § 1. 



but beyond this point the demarcation between the two gi-oxips cannot he clearly traced, the 



ridge to the North, which follows the average strike of the bedding, being covered with 



cotton soil. 



From Assoor to Purawoy the blue and yellow limestones, short bands of which protrude 



Limestones of Assoor and ^^^"^^ ^^^ soil and are largely quarried by the natives, are almost 



urawoy. ^j^^ ^^^ rocks exposed. They are very full of fossils, chiefly 



the two species of Pecten noticed at page 87, and a Gryphaea. In the broken ground South of 



Purawoy yellow shales and clays are seen to constitute the mass of the beds, dipping to the 



South-east at angles of from 2° or 3° to 15°. At this spot I obtained many of the characteristic 



Ootatoor Cephalopoda ; N. Forbesianus, N. Kayeanus, A. latidorsatus, 

 Fossils at Purawoy. 



A. Va)-una, fsee page 86,>' A. Mantelli ? A. Gautama, BaeuUtes, 



TMrnYefes, &c., with a few Gasteropoda, (Fleurotomaria, Natica, ^c.J and Conchifera, flnocera- 



mics, and Pecten 5-costatiis.J 



A small patch of coral-reef limestone occurs in situ close to the base of these beds, and in a 



band of conglomerate in the latter close by I noticed several 

 Conglomerate. „ „, , „, ^ . . 



large angular fragments of that rock, some of them containing 



corals. This is the only instance of a regular conglomerate I noticed about here. 



From Purawoy to the final disappearance of the group at Yylapaudy, limestone constitutes 

 the mass of the Ootatoor ^eds. For about a mile to the North 

 Olapaudy limestone. ^^ ^^^ fii-st-mentioned viUage, the prominent stony ridge formed 



by the out-crop of this rock is broken at intervals, the limestone being discontinuous and 

 occasionaUy replaced by clays and shales, but beyond this the limestone out-crop is aLnost 

 unbroken. The beds, as seen in some of the shaUow native quarries, are thick and massive, 

 somewhat jointed, though not, so far as I could determine, with any regularity in direction. 

 As is usual with the beds close to the base of the group, the dip is comparatively high. In 

 a small native quarry near Vapoor, exposing a section of 7 or 8 feet, the dip was about 20° 

 away from the gneiss ; in another smaU quarry near Olapaudy the dip was similar in amount, 

 while at the head of the little nullah that feeds the Vapoor tank it was 15°. The limestone is 

 variable in grain. Much of it is coarsely granular, and appears to be composed principally of 

 frao-mentary shells. In this variety entire shells or recognizable fragments are scarce : the 

 few I have seen in it consist of the Gryphssa ( G. columba?) Pecten (5-costatus) and another allied 

 species : the lowest bands immediately resting on gneiss, sometimes contain a few pebbles 

 of that rock up to the size of a small plum, but there is no regular conglomerate. Another 

 variety of the limestone is finer in grain and sub -crystalline, and the included fossils are likewise 

 rare. They consist chiefly of the above-mentioned species. 



Just East of Olapaudy pale grey sandy shales or clays, with strings of kunkur, crop 

 out from beneath the limestone and spread over a large area of ground 

 Shales at Olapaudy. ^^ ^^^ ^^^^^ ^^ ^^^ village. In a little nullah which drains the ridge 



where it is crossed by the road to Cootoonoor, limestone is seen resting on a mass of grey 

 sand, and this again resting on the shales with apparently a slight unconformity of dip. Only 

 two or three yards of the limestone and sand are exposed before these again are covered up 

 by the bottom conglomerate of the Arrialoor group. {See Fig. 10.) The shales are again seen 

 in another little branch of the same millah, a few hundred yards to the North, and on the open 

 ground half a mile North of the village some irregular bands of coarse grey calcareous grit, 



