160 PROF. W. N. BENSON AND DR. S. SMITH ON [vol. lxxix, 



west by an almost meridional and remarkably continuous fault. 

 This fault formed the channel along which has flowed the peridotite, 

 now converted into serpentine. Adjacent to the serpentine sheet 

 the folds of the Devonian are closely packed, although they show 

 little overfolding, but farther west they pass into gentler flexures. 

 Long, narrow, doubtless synclinal strips of Carboniferous rocks 

 have been nipped into the folded Devonian beds near the serpen- 

 tine, and in one of these strips the fossils from Hall's Creek (see 

 figs. 1 & 2, pp. 158, 159) were found. The chief development of 

 the fossiliferous Lower Carboniferous rocks, however, forms a 

 broad synclinal zone running parallel to the serpentine-belt, and 

 20 miles west of it, and in the axis of this syncline rises a ridge of 

 the Kuttung rocks. The locality, Slaughterhouse Creek, is on 

 the eastern flank of the syncline, and near the northern margin of 

 our area (see fig. 1, p. 158). The type-locality Burindi is also 

 on the eastern flank, 60 miles south of Slaughterhouse Creek, and 

 Moorowarra and Babbinboon lie 40 miles still farther south, 

 Moorowarra being on the eastern flank of the syncline and 

 Babbinboon on the western. 



It is not possible as yet to divide the marine Carboniferous 

 sediments into faunal or lithological zones, nor do the conditions 

 seem such as would promise much success if an attempt were made. 

 While we may, therefore, consider that the last four localities 

 mentioned are situated approximately on the same formation, the 

 thickness of which may be measured in thousands of feet, it is only 

 by inference that Ave may group with them the fossiliferous beds 

 •at Hall's Creek. The description of the Burindi fauna has been 

 the work chiefly of Prof. L. Gr. De Koninck; Robert Etheridge, 

 Junr., Mr. W. S. Dun, and Mr. J. Mitchell, and ourselves, and 

 our knowledge concerning it has recently been summarized by one 

 of us. 1 It consists of about 300 species, principally corals, bryozoa, 

 brachiopods, molluscs, and trilobites, other groups being sparsely 

 represented. It forms quite a representative development of the 

 ■Culm fauna, and the affinities of the majority of the species are 

 with Eurasiatic types, showing very little in common with the 

 Carboniferous faunas of America. It contains a small proportion 

 of forms which seem to be modifications of the Upper Devonian 

 littoral fauna that is developed in the central, southern, and western 

 parts of New South Wales ; but no characteristic Tournaisian 

 forms have been found. The whole fauna, indeed, seems to be of 

 Visean age, and the Burindi Series should, therefore, be referred 

 to the higher part of the Lower Carboniferous. There 

 are no forms that characterize the Upper Carboniferous, such as 

 Fusiilina, found in Eastern Asia ; and there is very little affinity 

 with the succeeding ' Permo- Carboniferous ' marine fauna, the 

 origin of which and its relationship to the Burindi fauna has been 

 discussed by Sir T. W. Edgeworth David (op. jam cit.). 



Summarizing the foregoing remarks, we may re-state the general 



'-W. N. Benson, 'A Census & Index of the Lower Carboniferous Burindi 

 Fauna ' Eec. Geol. Surv. N.S.W. vol. x, pt. 1 (1921) pp. 12-74. 



