摘要:

Alcheringais a new journal of palaeontology published by the Association of Australasian Palaeontologists of the Geological Society of Australia. The journal has two aims: to publish high quality interpretative palaeontology and biostratigraphy; and to provide a medium for the documentation of fossils from the Australasian area.

ISSN:0311-5518    

DOI:10.1080/03115517508619476

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

The fossil lycopodPleuromeia longicaulis(Burges) comb. nov. and its supposed coneCyclostrobus sydneyensis(Walkom) Helby & Martin 1965 are common in the Scythian to Anisian Garie and Newport Formations north of Sydney, N.S.W.P. longicaulisprobably lived in extensive monodominant stands in the interdistributary bays of the ‘Gosford delta’ system, bordering a large coastal lagoon or lake.C. sydneyensiswas borne as a single erect terminal cone. It was shed intact and may have floated some distance before breaking up and releasing its heterospores.

ISSN:0311-5518    

DOI:10.1080/03115517508619477

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

The cateniform tabulate coralsHalysitesandCystihalysiteshave normal corallites and an intercorallite coenosteum of tubules or dissepimental tissue (the mesocorallites or microcorallites of most earlier workers). Study of several specimens, chiefly from the Silurian of Gotland, reveals that the two genera exhibit markedly different patterns of lateral and interstitial increase. In lateral increase ofCystihalysites, corallites and intercorallite dissepimental tissue develop alternately along the base of a new rank. On the other hand, the corallites ofHalysitesoccur along the bottom of the new rank with intercorallite tubules inserted above the base. In interstitial increase ofCystihalysitesthe intercorallite tissue is vertically continuous, bifurcating to either side of the newly-formed corallite. In contrast, there is a gap in the vertical continuity of intercorallite tissue inHalysites. A tubule is replaced by a new corallite; then at a higher level, two new tubules become inserted to either side of the new corallite. Differing interpretations of the manner of development of both lateral and interstitial increase inHalysitesdepend on whether the polyps originally lived in shallow or deep calices.

ISSN:0311-5518    

DOI:10.1080/03115517508619478

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Eight fossil associations of larger foraminiferids have been recognised in Western Australia. Each represents a certain environment. Three of these associations were typical of seagrass communities at depths of less than 12 metres: theLepidocyclina (Eulepidina) ephippioides-Heterostegina borneensisassociation in oceanic salinities but in sheltered situations, theLepidocyclina (Nephrolepidina) howchini-Cycloclypeus eidae/carpenteriassociation in the same salinities but in open situations, and theLepidocyclina (Nephrolepidina) howchini-Marginopora vertebralisassociation in metahaline salinities. Two associations were typical of high energy sandy substrates in depths of less than 30 metres: theOperculina complanata-Gypsina howchiniassociation in oceanic salinities and theAustrotrillina howchini-Flosculinella bontangensisassociation in metahaline salinities. Three associations were typical of open situations with oceanic salinities. TheLepidocyclina (Eulepidina) badjirraensis-Cycloclypeus eidaeassociation lived in waters deeper than 12 metres; its lower boundary overlapped theCycloclypeus eidae-Operculina complanataassociation, which ranged to near the base of the euphotic zone at depths near 120 metres. TheOperculina complanata-smaller benthonic foraminiferal association was typical of depths near 120 metres or greater.

ISSN:0311-5518    

DOI:10.1080/03115517508619479

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Large fossil structures occurring commonly on certain bedding planes in the Arumbera Sandstone southwest of Alice Springs are described asArumberia banksigen. et sp. nov. These structures are interpreted as the remains of cupshaped animals, probably of coelenterate grade, that resemble two genera described from the Nama Group of South-West Africa and one from near Lake Baikal, Siberia.

ISSN:0311-5518    

DOI:10.1080/03115517508619480

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Poorly preserved scleractinian corals and cephalopod molluscs occur in metamorphosed and foliated limestones in the Himalayas of northwest India. The nautiloidCenocerasand macrocephalitid ammonites indicate a Middle Jurassic age. The fossils occur within a zone of high grade metamorphic rocks known as the Central Gneiss, previously regarded as an axial massif of Precambrian basement. Most palaeogeographic reconstructions feature this zone as a prominent topographic arch or ‘Himalayan Ridge’ which arose in the late Precambrian or early Palaeozoic and, through periodic rejuvenation, persisted throughout the Phanerozoic. Many workers believe that the ‘Himalayan Ridge’ constituted an effective barrier to north-south faunal migration because the terrains of sedimentary rock which flank the Central Gneiss contain quite different faunas. The Jurassic fossils provide new stratigraphic evidence that the tectonic events which generated the Central Gneiss are relatively young, and this, together with structural considerations, precludes the emergence of a ‘Himalayan Ridge’ prior to this time. Other evidence shows that the Central Gneiss was generated in the Tertiary, and suggests that the faunal contrast between the Lesser and Tethyan Himalayas reflects a tectonic juxtaposition of dissimilar sedimentary terrains that were previously separated by many hundreds of kilometres.

ISSN:0311-5518    

DOI:10.1080/03115517508619481

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Some of the basic tenets of cladism (phylogenetic systematics) and the techniques that have been used to apply them to palaeontological data are examined. Using as an example the studies by Eldredge of phacopids, the most complete and rigorous work yet published on Palaeozoic invertebrates using cladistic methods, it is concluded that the results are ambiguous, and that the geological inferences involving speciation and migration in northeastern U.S.A. are independent of the cladistic models.

ISSN:0311-5518    

DOI:10.1080/03115517508619482

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

New collections of Late Devonian age, from the Canning Basin, Western Australia, permit an examination of the evolutionary origin of stratigraphically important palmatolepan elements in terms of reconstructed apparatuses. The apparatuses conform to the polygnathid plan of Klapper & Philip (1971, 1972) and are described in such terms. The reconstruction ofMesotaxisKlapper & Philip (based onPolygnathus asymmetricus) is emended to an apparatus with a lippertiform N element and a ramiform symmetry transition series. Early forms ofPalmatodella(here used to include all apparatuses with a palmatolepan P element) possess a similar lippertiform N element, a palmatodellan O element, and a symmetry transition series clearly derived from that ofMesotaxis. InPalmatodella triangularisthe N element is lost and is not represented in younger Fammenian species ofPalmatodella. It is considered premature to attempt to relate the new reconstructions to a detailed generic taxonomy.

ISSN:0311-5518    

DOI:10.1080/03115517508619483

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor