III.—On some new Trilobites from the Upper Cambrian Rocks of North Wales
نویسندگان
چکیده
منابع مشابه
Phosphatised olenid trilobites and associated fauna from the Upper Cambrian of Västergötland, Sweden
Secondarily phosphatised olenid trilobites from organic−rich limestones (orsten) in the Furongian (Upper Cambrian) of Västergötland, south−central Sweden, are described and illustrated. All trilobites originate from the Peltura scara− baeoides Zone and were collected on the western slope of Kinnekulle. Only the dorsal exoskeletons have become second− arily phosphatised, and the ventral appendag...
متن کاملControls on Gut Phosphatisation: The Trilobites from the Weeks Formation Lagerstätte (Cambrian; Utah)
Despite being internal organs, digestive structures are frequently preserved in Cambrian Lagerstätten. However, the reasons for their fossilisation and their biological implications remain to be thoroughly explored. This is particularly true with arthropods--typically the most diverse fossilised organisms in Cambrian ecosystems--where digestive structures represent an as-yet underexploited alte...
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This paper presents a phylogenetic analysis of the ‘‘Fallotaspidoidea,’’ a determination of the biogeographic origins of the eutrilobites, and an evaluation of the timing of the Cambrian radiation based on biogeographic evidence. Phylogenetic analysis incorporated 29 exoskeletal characters and 16 ingroup taxa. In the single most parsimonious tree the genus Fallotaspidella Repina, 1961, is the s...
متن کاملThe Essence of the Cambrian Explosion
The fossil record of the Cambrian Period has been known as a problem for evolutionary thegfory since Darwin’s Origin of Species in 1859. Darwin was aware of the sudden appearance of complex animal forms in the Cambrian from his own collecting in northeastern Wales. Complex animal forms such as trilobites seemed to appear with geological suddenness with no apparent ancestors in older rocks below...
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ژورنال
عنوان ژورنال: Geological Magazine
سال: 1867
ISSN: 0016-7568,1469-5081
DOI: 10.1017/s0016756800205748