![]() ![]() Polyzoans are abundant in New South Wales ( Phillips-Ross, 1961), and species of Austrophylloporina, Batostoma, Homotrypa, and Stictopora show resemblances to North American forms. The post-Canadian faunas of Tasmania and New South Wales have much in common, particularly the corals Eofletcheria, Tetradium, Lichenaria, Nyctopora, Calapoecia, and Coccoseris, which are not known elsewhere in the continent, but are widely distributed in other parts of the world ( Hill, 1955, Hill, 1957 a). In addition there is a prominent endemic trilobite fauna. The nautiloids of the Tasmanian Manchuroceras-Piloceras fauna are of east Asian type, but the brachiopods Tritoechia and Syntrophopsis have American affinities. The nautiloids of the Georgina and Amadeus Basins which cover much the same time range are, however, clearly boreal in type, while the trilobites and brachiopods of the Amadeus Basin include a strong indigenous element along with others with cosmopolitan, Asian, and American affinities (Tomlinson, pers. For example, of the 24 genera of nautiloids described, 11 are indigenous, 2 are also known from Europe, and 10 are known elsewhere only from North America. ![]() The Canadian–lower Trentonian rocks of the Canning Basin are remarkable for the similarity of their nautiloid faunas to those of North America. ![]() They are best discussed on a regional basis. In contrast to the graptolites, the shelly faunas are limited in their distribution, and have not been comprehensively studied. Provincialism seems to disappear with the Nemagraptus gracilis zone, since it and all subsequent zones can be recognized throughout the world. * In the pre- Nemagraptus gracilis interval the affinities of the faunas are more with western and central North America ( Thomas, 1960 Ross and Berry, 1963 Skevington, 1963) than with western Europe, though it is possible to establish general correlations between all regions at certain points by widespread species or assemblages, such as the Dictyonema-anisograptid assemblage of the Tremadocian, the Tetragraptus approximatus assemblage and the first appearance of Isograptus in the Arenigian, and the Glyptograptus teretiusculus assemblage in the Llandeilan. The absence of this latter stage is the only significant gap in the New Zealand Lower Ordovician sequence. In Victoria the sequence up to the zone of Nemagraptus gracilis is as complete, perhaps more complete, than any other in the world, and it has certain distinctive features for example, the absence of Dichograptus in the Lancefieldian, the long-continued evolution of four- and three-branched forms of Tetragraptus fruticosus, and the abundance of Oncograptus and Cardiograptus in the Yapeenian. The most complete successions occur in Victoria and New Zealand ( Table 3.1), but graptolite-bearing rocks are now known from all States (except Queensland), and from the Northern Territory. The graptolite faunas of Australasia are particularly comprehensive and abundant. CROOK, in The Geological Evolution of Australia and New Zealand, 1968 PALAEONTOLOGY AND CLIMATE ![]()
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