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 Diplograpsus pristis, His., Orthis testudinaria, Dalm., and other Cambro-Silurian fossils; and as these shales are very similar in lithological characters to the shales at Shineton, and have the same general strike, both shales were lumped together by him as Lower Caradoc. This lithological resemblance is evidently the chief cause of the errors of the surveyors. On closer inspection, however, it is seen that the shale at Harnage contains a distinct fauna from the Shineton shales. The most abundant fossils of the Harnage shales, collected near Boomcroft and in the Hacrnage and Cound-Brook area, are Trinucleus concentricus, Eaton, Beyrichia complicata, Salt., Primitia bicornis, R. Jones, Orthis testudinaria, Dalm., Theca, several species of Lamellibranchs, Diplograpsus pristis, His., and Favosites flbrsus, Goldf. These are common Caradoc forms, and it is perfectly clear that the shales containing them are at Caradoc age. In no case are these fossils found in the same beds as those which contain the older fauna presently to be described. It is necessary to call attention to this point, as the Rev. J. D. La Tonche, president of the Caradoc Field Club, in his annual address in February last, has suggested some criticism on my conclusions, basing it on a supposed admixture of the older and younger faunas. There are no signs whatever of such admixture. The Tremadoc fauna ends abruptly upwards; the Caradoc fauna ends abruptly downwards; and not a single distinctively Arenig or Llandeilo species has been found in the district.

The Caradoc rocks of this area are much disturbed and faulted, and on Cound-Brook they are inverted, the older vesting to the younger at a considerable angle, and, in one or two spots, Shineton shales are strangely wedged in between Harnage shales. Farther details may he seen in my published paper (p. 656); but the Caradoc formation in South Shropshire deserves to be the subject of a separate memoir, recent observations haying considerably modified some of the conclusions of Aveling and Salter.

The locality where I first observed these shales is the spot near Shineton marked on the Geological Survey Map with an arrow dipping to the south-cast at 50’. The rocks are there exposed in two good sections on the left bank of the stream. It is from these sections that most of the characteristic fossils have been obtained; and I have, therefore, named the formation from its locality,

1.—Area.—These shales cover an area extending from near Eyenwoad, on the south-west, to within a mile of Wellington, on the north-east, a distance of eight miles. Their greatest breadth, from Shineton to Dryton, is abort two miles; but where they range towards Wellington it ig contracted alwnost to a point. The aca is roughly triangalar in shape, the apex of the triangle pointing to the north-cast. Its north-west side is bounded by a fault or fuulis for probably its entire length, various fenmutions from the Hollybush Sandstone to the Trius shutting against the shales. On the south-east side the Wiauele is covered in by intrasive lvasaltie voolks for one-third of its distance from the apex, ant the remainder by the May Hill Sandstene. The base of the triangular area