Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/239

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PRESTWICH—CRAG-BEDS OF SUFFOLK AND NORFOLK.
125

sand and flaggy limestone is worked in a pit a few yards to the south-east of the barn at the extreme south-west point of Gedgrave Hill. The shelly beds, with flags of shelly limestone at Tattingstone (see section in Part II.), may possibly be referred also to zone d.

"With regard to the bed of phosphatic nodules, it is no longer exposed at Sutton, and it has not been reached in any of the pits in the neighbourhood of Orford; but there is a shallow pit now worked between Butley Abbey and Butley River, which may probably belong to the base of the Coralline Crag; the crag-beds themselves have been removed, with the exception of a foot or two, which is so disturbed as to render its identification doubtful. Still, from the abundance of Cardita senilis, Astarte Omalii, and Cyprina islandica, the occurrence, although rare, of 'Mytilus hesperianus', Pecten maximus, and Isocardia cor, and the absence of the ordinary shells of the Red Crag, with the exception of a few specimens of Trophon antiquus, near the surface, I should feel disposed to consider this a disturbed portion of the Coralline Crag, and to refer the 2-foot coprolite-bed below it to this formation.

Organic Remains.

The Mollusca of the Coralline Crag have been worked out by Mr. Searles Wood with so much skill and perseverance that there is little


    • Pectunculus glycymeris.
    • Limopsis aurita (rare).
    • —pygmaea.
    • Nucinella miliaris.
    • Arca pectunculoides.
    • Nucula laevigata, var.
    • —tenuis?
    • —nucleus.
    • Leda pygmaea.
    • Kellia ambigua.
    • — —, large var.
    • Montacuta bidentata.
    • —truncata.
    • —substriata.
    • —ferruginosa.
    • Cryptodon sinuosum.
    • Lucina borealis.
    • Diplodonta rotundata.
    • —dilatata.
    • Cardium nodosum.
    • —strigilliferum.
    • —decorticatum.
    • Cardita senilis.
    • —scalaris.
    • —orbicularis.
    • —corbis.
    • — —, var.
    • Erycinella ovalis.
    • Astarte triangularis.
    • —parvula.
    • —Basterotii.
    • —mutabilis.
    • —Omalii.
    • —gracilis.
    • Astarte Burtinii.
    • —? digitaria.
    • —parva.
    • Cyprina islandica.
    • —rustica.
    • Circe minima.
    • Cytherea rudis.
    • Venus imbricata.
    • —casina.
    • —ovata.
    • Gastrana laminosa.
    • Donax politus.
    • Tellina obliqua.
    • —donacina.
    • Syndosmya prismatica.
    • Mactra obtruncata.
    • —triangulata.
    • Lutraria elliptica.
    • Solen ensis.
    • Thracia phaseolina.
    • —inflata.
    • Pholadomya hesterna(?).
    • Corbula nucleus.
    • Saxicava? carinata.
    • Glycimeris angusta.
    • Terebratula grandis.
    • Ditrupa subulata.
    • Balanus concavus (retaining colour).
    • —bisulcatus (common on Lucina and Pecten Gerardii).
    • Cellepora edax.
    • Hornera infundibulata.
    • Cupularia porosa.