160 FISH-REMAINS FROM "ROLLING DOWNS FORMATION" OF N. Q. 



I have much pleasure in affixing to this interesting fragment 

 the name of my former colleague, Mr. William Davies, F.G.S., 

 late of the Department of Geology, Natural History Museum, 

 London, and whose knowledge of extinct Ichthyology is probably 

 exceeded by no one. 



Locality. — Richmond Downs, Flinders River (Mr. C. de Vis- 

 Coll. Queensland Museum, Brisbane). 



In the report previously quoted, Mr. Jack makes the following 

 remarks on the Rolling Downs Formation * : — " Without enter- 

 ing fully into the question of the geological age of the Downs, I 

 may mention that I believe the strata to form one continuous 

 series representing part of the Cretaceous and Oolitic formations. 

 Apparently they form from east to west a large synclinal trough, 

 with an axis crossing the Flinders in the neighbourhood of 

 Marathon, At the heads of the Flinders the lowest beds do not 

 crop out, as they overlap the Palaeozoic and Metamorphic rocks 

 of the dividing range, and are covered by the basalt of the table- 

 land. To the west of Richmond Downs, however, a gentle dip to 

 the east brings up to the surface a sei'ies of strata which appar- 

 ently occupy a lower horizon than those in the centre of the 

 trough. From Hughenden to Marathon the strata consist for 

 the greater part of grey shales, with nodules of magnesian lime- 

 stone, and grey and brown sandstones, which are occasionally 

 calcareous and nodular. Near Richmond Downs, where an 

 ea-sterly dip is for the first time distinctly observable, the lime- 

 stones take a different character, and are distinguished by a 

 cone-in-cone structure. Further west there are fewer shale beds, 

 and thicker and browner sandstones. The latter ai-e extensively 

 veined with gypsum ; and I have been informed by squatters and 

 others that beds of gypsum are frequently met with in sinking 

 wells. The whole series is fossiliferous." 



* Loc. cit., p. 2. 



