Page:Quarterly Journal of the Geological Society of London, vol. 31.djvu/85

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IN THE ISLE OF PORTLAND AND AROUND WEYMOUTH.
39

IN THE ISLE OE PORTLAND AND AROUND WEIMOUTH. 39 inclined northwards, but occasionally has a dip southward and westward. The Kimmeridge Clay (K), which is squeezed up in low ridges in two or three places at the base of the cliff, rises at the south end of it until it is lost under the Portland Sands on the face of the escarp- ment. Up the slope so formed the angular debris extends to a height of about 200 feet, at which level it gradually thins off, leaving a slight depression or hollow free from the debris, between it and the slope of the escarpment (see woodcut, fig. 8, and Section 5, PI. I.). At first sight nothing can seem more unpromising for the discovery of fossils ; but I found them in two places, viz. at s (fig. 6), and again higher up, at a depth of about 12 feet from the surface and 80 feet above the base of the debris, in a bed of sandy loam under- lying a large boulder. At the latter they consisted of the following species : — 1. Bitkinia tentaeulata, Mullet : opercula. 2. Planorbis parvus, Say,=~P. gla- ber, Jeffreys. 3. Limnaea peregra, Mull., var. rnaritima. 4. Pupa raarginata, Draparnaud. 5. Candona Candida. 6. Cypris Browniana. Foraminifera. In the former, s, they occurred in a small intercalated bed of brown loam near the base of the cliff and 50 feet deep in the debris. Here they were very rare, and of only one species, Pupa marginata — together with one undeterminable leaf-impression ? This angular debris stretches only a short distance inland in the direction of the Verne, and is quite disconnected with the talus (T, fig. 8) formed by the existing cliffs or escarpment. I believe, Fig. 7. — Section at Sue/ton Pit near Southwell. 1. Black earth with weathered fragments of Purbeck strata 2. Broken Purbeck in angular fragments, passing down- i wards into 3. Undisturbed Purbeck beds... 6 feet. 10 feet. 4. Dirt-bed U foot. 5. Portland Stone 50 feet. however, that the broken and disturbed state of the upper 2 to 3 feet of the fissile Purbecks in all the higher parts of the island is part of the same phenomenon. In the small valley passing down by