lvi. 



of Upper Murravian fossils present iu the Muddy Creek beds 

 justifies the assertion made last year (Phil. Soc, p. 121) that 

 the upper marine strata exposed in the River Murray cliffs are 

 the direct equivalents to the Muddy Creek beds. Having thus 

 brought the youngest member of our Older Tertiary into 

 co-relation with the Muddy Creek beds, the next step in the 

 inquiry is to ascertain the age of the latter, the much larger 

 number of fossils contained in which makes this indirect 

 method the more satisfactory. The Victorian geologists do 

 not seem agreed on this point. McCoy oscillates between 

 Upper Oligocene and Older Pliocene, whilst Selwyn regarded 

 the Muddy Creek beds as the oldest of the Tertiaries in 

 Victoria, an opinion with which I do not concur. The proximity 

 of the Older Tertiaries of Tasmania, which occur on the north 

 coast at Table Cajie, to the Older Tertiary deposits of Victoria, 

 suggests the propriety of correlating them with those of the 

 mainland ; and so far as the examination of a limited number 

 of their fossils goes, I consider them to be the equivalents of 

 the Muddy Creek beds, and, therefore, probably of those at 

 Geelong. ]Sot having critically compared all the Muddy Creek 

 fossils with living forms I am not prepared to express more 

 than a tentative opinion on the proportion of living to extinct 

 sj>ecies ; but of the 288 species, eighteen are certainly recent, 

 or a little more than 6'2 per cent. I therefore think that we 

 may safely refer the Muddy Creek beds to the Miocene period. 

 Even by taking collectively the fossils in contemporaneous beds, 

 the proportion of living to extinct species is not more than six 

 per cent. The living species fossilised in these beds are as 

 follows : — 



The identification of those species marked by an asterisk (*) is on the 

 authority of the Eev. J. E. T. Woods, and those marked thus I on the 

 authority of Prof. McCoy, t Indicates that the author has examined the 

 species. 



Upper Aldinga. 

 Murray. 



1. Ancillaria Australis, Quoy *t 



2. *Syrnola bifasciata, Woods .. 



3. Cochlolepas foliaceus, Quoy . . *f 



4. *Liotia discoidea, Ev. ? 



5. Fissurellidea concatenta, 



Crosse *f 



6. Fissurella nigrita, Sow. 



7. Tugalia parmophoridea, 



Quoy *t 



8. Emarginula striatula *t 



9. Emarginula dilecta, Angas ? *f 



10. Cylichna australis, Quoy 



11. Cadulusacuminatus,Deshayes 



12. *Dentalinrnlacteum, Deshayes? 



13. Ostrea (cf) edulis, Lin. *t *t 



14. Pecten bifrons, Lk. . . *t 

 15. Pecten asperrimus, Lk. . . *f 



Muddy 

 Creek. 



*t 



Table 

 Cape. 



Keeent. 

 N. Zealand. 



* 



. . 



Tasmania. 



*t 



, „ 



S. Australia. 





* 



Tasmania. 



*t 



* 



S. Australia. 



•t 



•• 



S. Australia. 



*t 





S. Australia. 



*t 



. . 



N. Zealand. 





* 



S. Australia. 





*t 



Tasmania. 



*t 



*t 



S. Australia. 



•• 



•• 



India. 



Temp. Seas. 

 S. Australia. 

 S. Australia. 



