Mr Etheridgc on Fossils from Boiven River Coalfield . 317 



I shall conclude this portion of my subject by simply 

 quoting the view of the late Professor Jukes. Like Professor 

 Dana, Mr Jukes had the advantage of studying these beds in 

 sit It, in company with tlie Eev. W. B. Clarke, and his opinion 

 is therefore one of much importance. He regarded them as 

 the representatives of the British Silurian, Devonian, and 

 Carboniferous periods, or to use his own words, " I should for 

 the present hold the rocks of Australia now under considera- 

 tion simply as Pcdccozoic, and only assert that their age w^as 

 included within that of our Silurian, Devonian, and Carboni- 

 ferous periods."* 



It is now necessary to investigate the evidence afforded by 

 the Queensland fossils, and find what influence has the 

 frequent occurrence of Strophalosia on the question ? Accord- 

 ing to Mr Davidson this genus ranges in time from the 

 Devonian to the Permian inclusive and there dies out.f A 

 species has been described by the same author from beds 

 containing a copious carboniferous fauna in the Salt Piange 

 of the Punjaub, but so far as represented in the collection 

 examined by Mr Davidson, of rare occurrence.^ Mr J. S. 

 Miller § gives two American carboniferous Strophalosicc, S. 

 horrescens (Geinitz, non de Vern. and Keys.), and S. suhacu- 

 leata (Murchison), from the Coal Measures. The first of 

 these is not a Strophalosia at all, according to the researches 

 of the late Mr Meek, || but is identical with Productus nehras- 

 censis (D. D. Owen), at any rate the second clearly indicates 

 that there is at least one species of American carboniferous 

 Strophalosia. 



The above quotations show that Strophcdosia to a limited 

 extent occurs in rocks of Carboniferous age, but there is no 

 doubt that the genus " attained its greatest numerical develop- 

 ment in the Permian age, above which no authenticated 

 example has yet been discovered." ![ The preponderance of 

 so typically Permian a genus as StropJudosicc in the Bowen 



* Phys. Structure of Austr., p. 22. 



t Geol. Mag., 1877, iv., p. 260. 



X St. Morrisiana (King), Quart. Jour. Geol. See, xviii., p. 32, t. 2, f. 8. 



§ American Pal. Foss., p. 135. || Pal. E. Nebraska, p. 165, 



11 Davidson, Introduction, p. 116. 



