694 



THE SILURIAN TRILOBITES OF NEW SOUTH WALES, 



WITH REFERENCES TO THOSE OF OTHER 



PARTS OF AUSTRALIA. 



By R. Etheridge, Junr., Curator of the Australian Museum 

 — AND John Mitchell, Public School, Narellan. 



Part IV. 



The ODONTOPLEURTD^. 



(Plates L.-LV.) 



The next family we propose to take up is that of the Odoiito- 

 pleuridfe, adopting this name in preference to Acidaspid?e, because 

 we have every reason to believe it to have precedence. Burmeister 

 used the term in 1843, but we have not been able to ascertain at 

 how early a date Barrande employed that of Acidaspidte, with 

 which Zittel credits him. It could, however, hardly have been 

 before the date in question. The genera, or sections of the old 

 genus, Acidaspis, whichever the idiosyncrasy of the reader may 

 choose to regard them, are the following : — 



Ceratocejjhala, Warder, 1838. 

 Odontopleura, Emmrich, 1839. 

 Acidaspis, Murchison, 1839. 

 Dicranui'us, Conrad, 1841. 

 Selenopeltis, Corda, 1847. 

 Ancyropyge, Clarke, 1891. 



Of these we have been able to recognise in Australia only two, 



viz. : — 



Odontopleura, Emmrich. 



Ceratocephala, Warder. 



but possibly a third {Selenopeltis, Corda) may be represented l)y 

 our Ceratocephala lorigispina. 



None were described by Prof. L. G. de Koninck in his work 

 on the " Palaeozoic Fossils of N.S. Wales." 



