walcott.1 SOUTH AMERICA. 379 



Another pygidipm is identified as belonging to the genus Asaphus, and 

 small univalves which have the appearance of the genus Ophileta, of 

 Vanuxem. 1 



The trilobite8 and the gasteropods are correlated with the Upper 

 Cambrian fauna of America and Great Britain, to the Potsdam sand- 

 stone in America and the Lingula flags of Wales. 



In 1884 Dr. Henry Woodward described some trilobites from the 

 Parara limestone of the Yorke Peninsula, South Australia, Conocepha- 

 lites australis and Dolichometopus tatei. 2 He concludes that the trilo- 

 bites are clearly of Lower Silurian age, being equivalent to the Swedish, 

 Bohemian, Tasmanian, and North American beds with similar fossils. 



A recent paper by Mr. R. E the ridge, jr., on some Australian species 

 of the family ArchaBocyathinae describes the presence of several species 

 of that family in association with trilobitic remains at Ardrassan, Yorke 

 Peninsula, South Australia. The species described are Eihmophyllum 

 hindei, Protopharetra f scoulari and Coscinoci/athus tatei. 3 



The strata containing the fossils are correlated with the Potsdam 

 horizon sandstone of America or the Lingula flags of Wales. From 

 the stratigraphic position of the American forms of Ethmophyllum 

 and Cosciuocyathus it is quite probable that the Australian species 

 belong to the Lower Cambrian fauna and not to the Upper, as identi- 

 fied by Mr. Etheridge. 



SOUTH AMERICA. 



In 1876 Dr. Emanuel Kayser described a small collection of Primor- 

 dial fossils made in the northern portion of the Argentine Republic, in 

 the provinces of Salta and Jujuy, by Prof. Loreutz and Dr. Hyeroni- 

 mus, of Cordova. The fossils occur in a micaceous saudstoue, and. in- 

 clude the genera Lingula, Obolus, Orthis, Hyolithes, Arionellus, Agnos- 

 tus and Olenus. 4 Dr. Kayser compares the fauna with that of the north 

 of Europe and North America, and concludes that it belongs to the upper 

 zone of the Primordial. He calls attenti on to the fact that the genus 

 Paradoxides is wanting and that Olenus appears in great numbers. 

 "This fact seems to indicate that our fauna belongs to the upper Pri- 

 mordial zone or the Olenu s stage." 5 



A glance at PI. I, of Dr. Kayser's memoir proves that he is correct in 

 the reference and that the fauna is of the type of the Upper Cambrian. 

 From the geographical position and character of the fauna it is quite 

 probable that Cambrian formations will be found on the eastern slope 

 of the Andes, as well as the Cordillera of Central America and Mexico, 

 if not concealed by later deposits. 



tPapei 8 and Proc. Royal Soc. Tasmauia for 1882, 1883, pp. 151-158. 



'Note on the remains of trilobites from South Australia. Geol. Mag., new series, dec. in, vol.1, 

 1884, pp. 342-344. 



3 On some Australian species of the family Archasocyathina). Trans. Roy. Soc. South Australia, 

 vol. 13, 1890, pp. 10-22, Pis. II and ill. 



4 Beitrage zur Geologie und Palaeontologie der Argentinischen Republik; n. Palaeontologische 

 Theil. ; von Dr. Emanuel Kayser, Cassel, 1876, pp. 28. 



«Op.cit.,p. 29. 



