CHAP. 3.] KARNÜL FORMATION.—JUMMULMUDGOO GROUP. 69 
or traces of such. As in the ease of the limestone flags, however, 
the observer may have his curiosity whetted by finding occasional 
assemblages of exceedingly thin discoid bodies of about a sixteenth 
or an eighth of an inch 1n diameter, and generally of a dark brown color 
spread out on the surfaces of some of the lamins. These are somewhat 
like cycloid scales of fish; but no organic structure has been recognized 
in them. There are also frequent layers of small pisolitic concretions 
scattered through the more compact grey and purple shales. 
The lateral extent of the Owk shales is much greater than that of 
the overlying quartzite group, for their outcrop is 
seen showing up from between the Koilkoontlas 
and their own associated limestone beds, along the southern half of the 
Extent of shales. 
eastern side of the Khoond-air valley ; there never being in any exposed 
section the least trace of quartzites of any kind except those of the 
bottom of the KARNÚL and of the kApAPAH formations. 
The greatest thickness known of these shales is about 50 feet, 
that is of the buff, white, and purplish beds. 
There are from 20 to 30 feet in the hills above 
and behind the village of Owk* (whence the name of the sub-division 
50 feet of O wk shales. 
is derived) ; 30 to 40 feet in the south-west scarp of the Oopalpád plateau ; 
40 feet on the eastern slope of the long outlying flat-topped hill due 
south of Oopalpad; 30 feet in Colimgoondla hill,t and 40 to 50 feet 
in the most southerly of the other flat-topped hills south of Koilkoontla. 
In the outcrop of the shales along the eastern side of the Khoond- 
air valley, it is seen that they are cleaved in the 
same way as is the case with the Nundials, only 
this feature is not so well exposed as in the upper shales; neither does 
it appear that they are so well cleaved. The Nundial shales are, as 
Cleaved. 
already shown, very much cleaved, almost to the obliteration of bedding in 
* Owk is a large village in the Koilkoontla taluq, Kurnool district, on the extreme 
western edge of the Khoond valley. 15? 12’ 30" N. Lat. and 78° 10' 30" E. Long. 
+ Colimgoondla hill, pagoda-crowned,-—about nine miles due south of Owk. 
(69) 
