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Transverse sections of Chirodipterus australis and Griphognathus whitei are used to demonstrate the histological structures of the rostral and symphysial tubuli in Devonian lungfish. The walls of the tubuli are composed of bony tissue indistinguishable from the cancellar bone found in dermal bone. It has many spaces and perforations, and is contiguous in places with the cancellar bone of the external dermal bone. The walls of lateral-line canals have the same histological structure as the walls of the tubuli; they also intercommunicate with them. The tubuli and the lateral-line canals open to the surface through large perforations on the external surface. In Griphognathus the walls of the tubes under the external dermal bone have two layers: the outer one is dense bone, but the inner one has the appearance of calcified fibrous connective tissue of the kind associated with the tissue surrounding the lateral-line canals in living lungfish. The tubuli are closely related to the pore-canal system via canals that penetrate the dermal bone; this same relationship has been observed in Dipnorhynchus and Speonesydrion. The intimate connection between the tubuli and the lateral-line system suggests that they were formed by the sinking of neuromasts into and under the external dermal bone, with their walls surrounded by cancellar bone.  相似文献   
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Several bones from the Late Pleistocene archaeological site, Kutikina Cave, in southwest Tasmania, show pathological conditions. The majority of these specimens represent Bennett's or red‐necked wallaby (Macropus rufogriseus), with a single specimen of the Common wombat (Vombatus ursinus) recorded. While there has been extensive work in this region of Australia since the early 1980s, this is the first record of palaeopathology from the late Pleistocene of Tasmania, and the first from a human accumulation of predominately macropod material. The palaeopathology raises several questions concerning the mobility of these animals which might have increased their susceptibly to predation, while some of the effected elements are fragmented, suggesting that people utilised these bones despite their deformities. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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Falling trees commonly turbate soils in primary forest, creating characteristic edaphic patterns related to pit and mound topography. Vernal ponds with associated mounds were observed in mineral soils on a treeless plain in subalpine Tasmania, Australia. The hypothesis that paired ponds and mounds on the plain originated as pit and mound features in forests that were later destroyed by fire was tested by comparing the soils and landforms caused by recent tree falls in adjacent forest with those on the plain. The soil characteristics, orientations, and dimensions of the ponds and mounds were consistent with a tree fall origin, although rare secondary ponds on the tops of mounds may derive from the burrowing activities of the medium‐sized marsupial, Vombatus ursinus (common wombat). The characteristics of pond and mound soils suggested that most were hundreds to thousands of years old, with the ponds persisting because of differences in deflation, deposition, and organic matter formation between themselves and adjacent persistently dry land.  相似文献   
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