AGE OF THE MESOZOIC ROCKS OF LAKE EYRE BASIN. 229 



with species described by Mr. Charles Moore,* from Wollumbilla, 

 Queensland. 



Since my first announcement of Secondary fossils in the Lake 

 Eyre basin, several small collections have been received from 

 widely separated localities, and the list of species has now attained 

 to fair dimensions. For the most part, the condition of the fossils 

 does not permit of accurate generic definition, and the same 

 remark applies equally well to those of Wollumbilla, described by 

 Moore, and those of Maryborough described by Etheridge. It is 

 not, therefore, always safe to refer our fossils to described species ; 

 and better definitions of the genera and species of the Secondary 

 fossils of Central Australia and Queensland is much to be desired. 

 Nevertheless, where specific identities are possible, the fossils of 

 the Lake Eyre basin are, for the most part, constituents of the 

 Wollumbilla fauna, whilst a few are common to the Maryborough 

 beds. 



The occurrence of Crioceras and a Ceratite-like Ammonite among 

 the common fossils of the Lake Eyre basin demands their relega- 

 tion, as also those of Wollumbilla, to the Cretaceous System. 



The Wollumbilla collection, offering no restricted Mesozoic types, 

 was regarded by Mr. Moore, on the strength of certain supposed 

 identities with the European Juras as Jurassic, and though admitting 

 the Cretaceous facies of the Crioceras, yet he attributed it to beds 

 of very much younger age than those at Wollumbilla. The recent 

 discovery, as already announced, proves Mr. Moore to have been 

 in error. The Jurassic age of the Greenough beds in Western 

 Australia is not likely to be challenged, and between them and 

 the Queensland Cretaceous beds there is no community. 



The European identities alleged to occur in the Wollumbilla beds, 

 are Lingula ovalis Avicida hraambiiriensis, Belemnites jxixillosus, 

 Serpnla intestinalis, and Rliijiichonella variabilis. Relying on Mr. 

 Moore's determinations, I have persistently advocated the Jurassic 

 age of the Lake Eyre fossils ; but forced to abandon that position 

 by the more decided Cretaceous facies of recently acquired species, 

 it becomes necessary to reinvestigate the claims of the foremen- 

 tioned species to bear the names attached to them. 



A well preserved pecimen of Lingula from the Lake Eyre Basin, 

 agrees exceedingly well with L. subovalis, Davidson ; a RhyncJio- 

 nella from the same area is certainly like some varieties of R. 

 variabilis, Schlotheim, but it differs by its depressed mesial 

 area, though at the same time I cannot attach it to any 

 described Cretaceous species. Moore's figure of Avicida braam- 

 buriensis does not I'epresent that shell at all, it may be a Pecten, 

 though it is certainly not Aucella lingliendensis. 



Bdemnites paxillosus, of Moore, is admitted by Phillips not to 

 be that species, indeed the oblique lateral grooves, and absence 

 of apical furrows places it in juxtaposition with B. australis, and 

 removing it far from the Liassic fossil, I name it B. eremos. 



* Quart. Journ. Geol. Soc. 1870, xxvi. p. 226. 



