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Late Ordovician graptolites are commonest in the Australian states of Victoria and New South Wales, occurring in sediments which are either folded into complex structures or else interrupted by massive thickness of volcanics and associated with frequent facies changes. Thus it has not been possible to construct a series of zones which have either continuity or an established order of appearance. Present knowledge also suggests that differences occur between coeval faunas from volcanic and no-volcanic strata. Silurian graptolites are most common and best preserved in New South Wales. The full sequence of graptolite zones devised in Britain cannot be recognized in Australia. This can be explained partly on failure of outcrop, and partly upon regional hiatuses. The most continuous Llandovery sequences are in areas with a widespread cover of Cainozoic volcanics and gravels. Nonetheless, the Llandovery zones so far recognized, principally cyphus-gregarius and turriculatus- crisplts, are very wide-spread and occur in differing environments, so that non-representation of zones cannot be attributed wholly to collecting failure. These zones are among those most readily recognized throughout the world, which probably results from their being based upon distinct, easily identified species, and their comparatively long duration. The Wenlock zones are those most poorly represented, this being the part of the Silurian in New South Wales and eastern Victoria most affected by orogenic activity. In areas of central Victoria where sedimentation is believed to have been continuous throughout the Wenlock, the sediments have suffered extensive bioturbation and graptolites are absent. In addition, the extreme rarily of Cyrtograptus means that it is often very difficult to tie an assemblage with an overall Wenlock aspect to any particular zone. The Late Silurian graptolites are those which are most widely distributed, and it has been possible to recognize most of the zones described from the Ludlow and Pridoli of Europe. Sedimentary sequences which cross the Siluro-Devonian boundary are common, but graptolites in Early Devonian strata are frequently in isolated beds separated by great thickness of non-graptolitic strata.
The Australian species classified in the cosmopolitan genus Scymnus are revised. Nomenclatural history, diagnoses, illustrations and distribution are provided for each of the eleven recognized species. Scymnus fuscatus Boheman, 1859 is recorded from Australia for the first time. Four new species, Scymnus alligator, S. bunya, S. leai and S. tasmanicus are described. Lectotypes are designated for: Midus pygmaeus Blackburn, 1892, Scymnomorpha duplopunctulata Blackburn, 1892, Scymnus ambulans Blackburn, 1895, S. mitior Blackburn, 1895, S. parallelus Blackburn, 1889, S. queenslandicus Blackburn, 1892 and S. varipes Blackburn, 1895. A new name Scymnus blackburni nom. nov. is introduced for Scymnus pygmaeus (Blackburn, 1892) preoccupied by Scymnus pygmaeus (Fourcroy, 1785). Scymnus varipes Blackburn, 1895 is recognised as a junior synonym of Scymnus ambulans Blackburn, 1895 (syn. nov.)
The paper reports on the occurrence of five Thermocyclops species in urban subterranean habitats in North Queensland, Australia: T. crucis sp. nov., T. pseudoperculifer sp. nov., T. rylovi (Smirnov), T. crassus (Fischer), and T. decipiens (Kiefer). Females and males of T. operculifer (Kiefer), a supposedly close relative of the Australian taxon T. pseudoperculifer, is redescribed based on the holotype (Lombok) and non-type material (Sulawesi) from Indonesia. Thermocyclops crucis sp. nov. and T. pseudoperculifer sp. nov. (tropical coast of Queensland) share the caudally spinulose ornamentation of P2-P4 couplers and bare PI coupler with T. operculifer (Indonesia: Lombok, Sulawesi) and T. uenoi (Japan: Kyushu, Tomogashima Island). Diagnostic values of the morphological characters used to define the 'schmeili-growp' sensu Mirabdullayev and Fiers, to which both new Australian taxa might be allocated, are discussed. Finding of T. rylovi known so far from East Africa, Central and South Asia, in a semiarid inland locality in Queensland, is the first record of the species in Australia. Descriptions and illustrations of the diagnostic characters of T. crassus and T. decipiens are provided, and the morphology of the Australian specimens is compared with that in the European and Southeast Asian representatives. An identification key to all Thermocyclops species occurring in Australia is added.
Variations of the branches of the aortic arch are likely to occur as a result of the altered development of certain branchial arch arteries during the embryonic period of gestation. In the present investigation the pattern of branches of the aortic arch was studied in 81 cadavers from a recent South Australian population of European descent, who have migrated to (n = 38) or were born and lived in (n = 43) South Australia during the twentieth century. Two principal variations were noted in the present study. Firstly, in 6 cadavers, the left vertebral artery originated directly from the arch of the aorta, between the left common carotid and the left subclavian arteries. The 6 subjects were among the subgroup born in South Australia, giving an incidence of 13.95%, which is much higher than in previous reports. The overall incidence of 7.41%, when related to the whole group, is also higher than incidences reported in other populations. The presence of this variation suggests that in some individuals part of the aortic arch is formed from the left 7th inter-segmental artery. Secondly, none of the cadavers examined had the thyroidea ima artery, contrasting with previously reported incidences that varied between 4% and 10%. Since all 6 cadavers with the left vertebral artery variant were born in South Australia, it is suggested that environmental factors may have contributed to this variation. Significant environmental changes in South Australia around the turn of the twentieth century are discussed. This study represents the first systematic investigation of the branches of the aortic arch in a South Australian population and provides data relevant to the practice of medicine.
The genus Pellenes is newly recorded from Australia. Its relationships are discussed and diagnostic drawings, redescription and distributional data for Pellenes bitaeniata (Keyserling, 1882), the only known Australian representative of the genus, are given.
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