is limited by the Hoar Edge Grits, the lowest beds of the Caradoc. I have recently detected the shales in the hollow between the Lawley and Hoar Edge, an the south-eat side of Caer Caradoc, and west of the Longmynd, at the base of the Stiper Stones.
2.—Lithological Characters.— Shineton Shales are dark blue, Weathering to olive and yellow, the colouring iron-oxide sometimes separating as a stain or film. They are micaceous, thin bedded, soft, and rather fissile. I have rarely had any difficulty in distinguishing them from the Harnage Shales, either in situ or in hand specimens,
3.—Dip and Strike.—The general strike of the shales is about south-west, agreeing with the direction of the great fault and of the so-called igneous elevations of the district; but towards the south-west end of the area it bends round to the west, corresponding with the strike of the overlying Caradoc. The mean dip of the greater part of the shales is about 30° to the south-east; but in the lower part of the series, where they approach the fault, it becomes higher, then vertical, than dips steeply to the north-west, the evidence pointing towards the existence of an anticlinal. The thickness of the shales is probably not loss than 1,500 feet.
4.—Stratigraphical Position.—The Shineton Shales underlie the May Hill Sandstone unconformably; they are therefore older than that formation by an interval. They underlie the Caradoc, and are, of course, of greater antiquity. They overlie, probably unconformably, the Hollybush Sandstone. I shall endeavour to show that they are of Tremadoc age.
(a.)—Evidence from Fossils.—Most of the Shineton forms are new specifically, and some of the genera are also new. The species which are of geological value are the following:—Conocoryphe monile, Salter. Conocoryphe proper is distinctive of Lower Cambrian rocks, and this species is truly typical of the genus. Olenus Salteri, Callaway, and O. triarthrus, Call., new species of a genus which usually characterizes strata of the age of the Lingula Flags. Agnostus dux, Call, similar to certain St. David’s forms, (Menevian.) Lingulella Nicholsoni, Call, resembling L. lepis, a Tremadoc species. Asaphellus Honfrayi, Salt., common in the Upper Tremadoc at Portmadoc.
(b.)—Evidence from Correlation with Rocks in other Localities.—Dictyoneum beds at Pedwardine.—Shales identical lithologically with the Shineton Shaleos, and containing Lingulella Nicholsoni, are found at Pedwardine, twenty-five miles to the south-west of Shineton, on the same line of strike, They also contain Dictyoneum sociale, which has not yet been found at Shineton.
Dictyoneum Beds at Malvern.—Overlying the Olenus Shales near White-leaved Oak, are light-coloured shales, similar to the Shineton and Pedwardine beds, and containing two Shineton forms, Platypeltis Croftii, Call., and Conophrys salopiensis, Call., together with Dictyoneum sociale, Balt,
A comparison of the three formations at Shineton, Pedwardine, and Malvern is very interesting. The Shineton beds are connected with the
