620 GREAT SERPENTINE-BELT OF NEW SOUTH WALES_, V., 



periods of activity, the first of which was also marked by the intru- 

 sion of massive and brecciated spilites, dolerites, and keratophyres. 

 Peculiar types of intrusive tuffs were constantly developed, and 

 their probable mode of origin is here discussed. At two or three 

 epochs, limestones were formed, and the fossil-content of these is 

 sufficiently varied to permit of their distinction on palseontological 

 grounds. The total thickness of the series cannot be exactly deter- 

 mined, owing to the presence of an indefinite amount of faulting. 

 An apparent thickness of over 12,000 feet of strata are of Middle 

 and Upper Devonian age. Folding and faulting occurred probably 

 in Carboniferous times. The movements were most pronounced 

 along an axis running N.N.W.-S.S.E., but there is clear evidence 

 of less important movements along a N.E.-S.W. axis. The folding 

 was followed by the intrusion of peridotite, succeeded by that of a 

 mass of granite, which produced interesting contact-metamorphism 

 of the tuffs and limestones. No further events are recorded until 

 the eruption of a small amount of basalt, probably during the 

 Tertiary period. The discussion of the physiography is reserved 

 for a future occasion. 



BIBLIOGRAPHY. 



1. Clarke, Rev. W, B. — Reports on the Goldfields of New South 



Wales, published in the Votes and Proceedings of the Legislative 

 Council, also in the Parliamentary Papers of Great Britain. 

 Further Papers relative to the Discovery of Gold in Australia. 

 N.S. W. Leg. Council, 1853-1858, i., pp.565-612; G.B. Pari. Papers, 

 Feb., 1854, pp. 42-55. 



2. De Koninck, L. G. — " Recherches sur les fossiles paleozoiques de la 



Nouvelle Galles du Sud (Australie)." Memoires de la Society 

 Royale de Liege, 2nd Ser., Tome ii., 1876-7. 



3. "Description of the Palseozoic Fossils of New 



South Wales " (translation of the above). Memoirs of the Geolo- 

 gical Survey of New South Wales, No. 6, 1898. 



4. Porter, D. A. — " Notes on some Minerals and Mineral-localities in 



the Northern Districts of New South Wales." Proc. Roy. Soc. 

 N. S. Wales, 1894. 



5. Etheridge, R., JcN. — "On-the Occurrence of the Genus Tryplasma, 



and another Coral, apparently referable to Diphyphyllum, in the 

 Upper Silurian and Devonian Rocks, respectively, of N.S.W." 

 Records Geol. Survey of N.S.W., Vol. ii., Pt.l, p. 15, 1890. 



