BY W. N. BENSON. 543 



and a thickness of 9,260 feet is stated to occur between the 

 anticlinal axis and Spring Creek in the Tamworth Common. 

 Here is a great fault, east of which the limestones appeared 

 again, followed by more radiolarian sediments and interstratified 

 igneous rocks. This limestone is shown to be on the same horizon 

 as that at Moore Creek, and is believed to be also the equivalent 

 of the limestone in Seven Mile Creek. The microscopical ex- 

 amination of the igneous rocks made by Mr. Card having 

 revealed their clastic nature, they are now stated to be felsitic 

 tuffs, but it is still held that they are often intrusive or crushed 

 into the sediments, and pictorial evidence of this is given. The 

 new view, however, removed them from any direct relation with 

 the Moonbi granites. While formerly Lepidodendron was found 

 only above the radiolarian rocks, it was now shown to occur 

 within them. On the grounds of the association of the radio- 

 larian chert with coral limestones, the absence of coarse terri- 

 ginous sediments, the abundance of plant-remains, and the 

 presence of ripple-marking, it was concluded that the radiolarian 

 rocks "were deposited in clear sea-water, which, though suffi- 

 ciently far from land to be beyond the reach of any but the finest 

 sediment, was nevertheless probably of not very considerable 

 depth." Finally, they discovered certain coarse agglomerates on 

 the hills to the north of Tamworth, which they considered to be 

 unconformable on the clayslates, and probably the basal beds of 

 the Carboniferous System. 



The radiolaria in these rocks were investigated by Dr. Hinde, 

 who described fifty-three species, all new to sciencedO). This 

 does not exhaust the radiolarian fauna of the district, however, 

 for additional forms, not yet described, have been noted by Pro- 

 fessor David and Dr. Jensen.* 



The fossils in the limestones at Moore Creek, Tamworth, and 

 Moonbi, collected by Messrs. David, Pittman, Porter, Beedle, 

 and Etheridge, were described by the last-named, who found 

 nineteen species of corals to be present, most of which were new 

 to science. He considered that the limestone of Moore Creek 



* Verbal communication. 



