On the Relative Distribution of Fossils throughout the North Devon Series
1867; Geological Society of London; Volume: 23; Issue: 1-2 Linguagem: Inglês
10.1144/gsl.jgs.1867.023.01-02.55
ISSN2058-105X
Autores Tópico(s)Paleontology and Stratigraphy of Fossils
ResumoI. I ntroduction A lmost all observers since the time of Messrs. Weaver and Williams, in 1837 and 1838, have shown that the slates, shales, and sandstones which constitute a large portion of the north of Devon differ so much in their lithological and mineralogical structure as to render it necessary to subdivide them into several successive zones or groups. In the ‘Palæozoic Fossils of Cornwall, Devon, and West Somerset,’ Prof. Phillips pointed out, by means of a synoptical table, the relative occurrence of fossils throughout these different subdivisions of the North Devon series, which he named the Lynton, Combe Martin, and Pilton groups respectively, each of these three fossiliferous beds being separated from each other by a considerable thickness of grits and shales, which have hitherto proved destitute of organic remains. More than a quarter of a century, however, has now elapsed since Prof. Phillips's work was published; and since that date not only have many new fossil-localities been observed, but so great a change has taken place in the system of nomenclature as to render it at present anything but easy for the geologist to identify the names of some of the species, or to ascertain in which group they occur. Thus the Leptœna caperata of Phillips was placed a few years later in the genus Strophalosia , and the name of the species has since been altered into productoides , so that in Strophalosia productoides of the present day no trace whatever of the original name can now be recognized. Again
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