342 C. A. SUSSMILCH AND W. G. STONE. 



Brachiopda ...Pentamerus(Conchiclium) Knightii 

 Gasteropoda... Palaeoniso Brazieri, Loxonema antiqua 



(?) Velotuba 

 Cephalopoda . . . Orthoceras, Lituites 

 Trelobita ...Sphaerexochus mirus, (?) Phacops. 

 These have been determined by Messrs. R. Etheridge, Jr. 

 and W. S. Dun. Of these fossils Pentamerus, Favosites, 

 and Stromatopora are the most abundant. 



The eastern bed of limestone, as already pointed out, lies 

 to the east of the cave limestone, and strikes about N. 20° 

 west, but it dips to the east at an angle of about 65°. It is 

 not so massive as the Gave limestone and is more definitely 

 stratified, there being frequent intercalation of beds of 

 shale. No fossils have yet been obtained from this bed. 



The relative position of these two limestone beds with 

 regard to one another and to the associated strata, indi- 

 cate that they are part of one and the same bed, the Cave 

 limestone occurring in the western leg of a great anticline, 

 the other occurring in the eastern leg of the same anticline. 



On top of the ridge formed by the Gave limestone, 

 remarkable examples of the "rills" or grooves formed by 

 the chemical action of rain-water upon the surface of the 

 limestone outcrops may be seen; some of these simulate in 

 a remarkable way the drainage system of a steep mountain 

 range; these are particularly well shown on the top of the 

 Lucas Rocks, and above the Carlotta Arch. 



2. The Slates. — These are typical examples of the so- 

 called Silurian slates of New South Wales, and are well 

 shown in the road-cutting on the Mount Victoria Road for 

 the last four miles before reaching the Caves. In colour 

 they may be light-grey, bluish-grey, red, or dark-green; 

 they are much jointed and usually break more readily along 

 the joint planes than along the laminations, but do not 

 possess the fissile structure of a typical roofing slate. The 



