BY A. B. WALKOM. / / 



(c) Ccmipariso'n of floras of the Ipsivirh and WaUoon Series. — - 

 We are now in a position to compare the fioras of the Ipswich 

 and Walloon Series. As a result of all previous examinations 

 of these floras, it has been observed that there was no palseonto- 

 logical distinction between the floras of the two Series; e.g.^ Mr. 

 Cameron states •* "It does not, however, seem possible to draw 

 any distinction between the formations from pala?ontological 

 evidence, most of the fossils as yet found in the Walloon Beds 

 occurring also in the Ipswich Beds." 



The failure to note palseontological distinction between the 

 two has been due, however, to imperfect collecting, and to the 

 fact that the material available has not been thoroughly ex 

 amined since the examination by Mr. Etheridge, prior to the 

 publication of the " Geology and Palaeontology of Queensland 

 and New Guinea," in 1892. In 1898, Dr. Shirley examined and 

 described a number of specimens, but all the Lower Mesozoic 

 specimens among them were from the Ipswich Series. The same 

 author, in 1902 recorded a few more specimens from the Ipswich 

 Series, and some from the Stewart's Creek Beds (of Walloon age). 

 At the time of these publications, however, there was no subdivi- 

 sion of the Ipswich Formation into Ipswich, Bundamba, and Wal- 

 loon Series, so it is not remarkable that no distinction of horizons 

 was noted in the upper and lower portions of the Formation. 



A glance at the following Tables (Tables vi. and vii.) at once 

 shows that there are points in which the two Series can be dis- 

 tinctly separated, and that there are a number of species char- 

 acteristic of each. These species, characteristic of only one 

 Series, are the more important ones from a stratigraphical point 

 of view, and the finding of some of them may, in the future, be 

 used for fixing the age of the strata in which they occur. 



<^)ueensland Ueol. Surv., Publication No.204, p. 16. 



