576 GREAT SEKPENTINE BELT OF NEW SOUTH WALES, ii., 



Folly Creek, it is 100 feet thick. The lower portion is of the 

 cavernous tuff-type, but the upper is a white crystalline lime- 

 stone, with thin bands of quartz and tuffaceous material. It is 

 followed by a narrow zone of fine breccia, covered by a great 

 thickness of cherty claystones. About half a mile east of this, 

 is a very narrow bar of pure, crystalline limestone. 



Tracing further to the southwards, we find a small bar cross- 

 ing the spur by the Swamp Creek Falls, and again a small patch, 

 with Diphyphyllum, in the angle above the Falls Both these 

 approximate to the cavernous type. Nothing further is seen for 

 two miles, then a tiny lens of cavernous rock is found on Ruzicka's 

 Hill ("Risky's Hill") near Hanging Rock. This is east of the 

 proper horizon. On the true horizon, a little limestone is to be 

 seen at the head of Spring Gully, in Stringer's Tunnel (Deegan's 

 lease), and, near here, some traces of brachiopods were found, in 

 the slate, too obscured for determination (fide Mr. W. S. Dun). 

 A few hundred yards further down hill, there is a small group of 

 lenses by the Devil's Elbow, on the Hanging Rock Road, with 

 obscure shells (one like Atrypa) and corals, including Hdiolites 

 porosa. One of these lenses is intruded by dolerite. A small 

 lens occurs in Oakenville Creek, and ascends the hill opposite the 

 cliffs of Hanging Rock. This is the southernmost occurrence 

 noted. A complete list of the forms observed is given in the 

 preceding Part. In the author's opinion, the limestone is not 

 only analogous to the Tamworth limestone, but is on the same 

 horizon. 



(d). The Upper, Banded, Radiolarian claystones lie on these 

 limestones. They form a well marked band about 1,000 feet 

 thick. They may be traced from north of Cann's Plains Creek, 

 across the Peel River, where they are well developed in Daylight 

 and Mahoney's Creeks, and form the great cliffs that overhang 

 the junction of Swamp Creek and Folly Creek. Here they are 

 often very cherty. Further to the south, they cross Oakenville 

 Creek, and are well developed near Mount Ephraim. They con- 

 tain abundant radiolarian casts. 



Interstratified with these, is a large amount of the tuff-breccia 

 identical in character with that below the limestone. 



