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The Cambrian sequence of the Świętokrzyskie Mts. (Holy Cross Mts.) is rich both in body fossils and trace fossils. The paper presents results of examination of all Lower Cambrian trace fossils except trilobite traces. The Lower Cambrian trace fossils include 19 ichnogenera (19 ichnospecies). Four new trace fossils have been described: Multilamella spatiosa ichnogen. et ichnosp. n., Elingua convexa ichnogen. et ichnosp. n., Cochlichnus annulatus ichnosp. n., and Cylindrichnus operosus ichnosp. n. The trace fossil communities were used to characterize the environmental conditions for each formation recognized in the Lower Cambrian sequence of the Świętokrzyskie Mts.
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The Late Cambrian eocrinoid Cambrocrinus

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Morphology of the stem in Cambrocrinus regularis Orłowski 1968 from the early Late Cambrian of the Holy Cross Mts, with only one type of columnals in its proximal conical part but with well developed marginal fulcra connecting them alternately in pairs, places it in between the Middle Cambrian Acadocrinus and Late Cambrian Ridersia. In the presence of thecal ribbing with ribs radiating toward plate corners, which is definitely not homologous to the ribbing of Ridersia, Macrocystella, and later cystoids, it departs from the main eocrinoid lineage leading to the rhombiferans. A new family Cambrocrinidae is therefore proposed to include Cambrocrinus and Eocystites.
During the Middle and Late Cambrian in the area of the present-day Holy Cross Mountains all the traces of infaunal activity were produced by animals burrowing parallel to and immediately below the sediment surface, deeper infaunal burrowers being missing. Deeper penetration was probably not possible due to anoxic conditions within the sediment. This was not the case in the Early Cambrian, where numerous deep vertical burrows with spreite structures are known in the area. Diversity of the Middle and Late Cambrian trace fossil assemblages of the Holy Cross Mts is low, with only six ichnogenera of non-arthropod traces in the Middle Cambrian and eight ichnogenera in the Late Cambrian, compared with 24 ichnogenera in the Early Cambrian. The most unusual is a large hemispherical burrow, possibly of actinian origin, for which the name Bergaueria elliptica isp. n. is proposed. Treptichnus rectangularis isp. n. represents horizontal burrows with stiff walls, being systems of short units connected with one another. Some of the units contain faecal pellets produced by the host animal.
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