. The Quarterly journal of the Geological Society of London . emont, the actual base is not seen ; but the rubbly un-stratified mass appears to begin at once. It is here full of unrecog-nizable Thamnastraaan corals (which appear to have been rolled), andabundance of Hemicidaru crenularis, Cidaris florigemma, ApiocrinusMoissyanus, Terebratula maltonensis, and Pecten vimineus. There isa thickness of about 120 feet, all made of similar material exceptnear the top, where about 16 feet is made of massive crinoidal lime-stone as near Verdun. This latter type, therefore, as there, is sub-ordinate to
. The Quarterly journal of the Geological Society of London . emont, the actual base is not seen ; but the rubbly un-stratified mass appears to begin at once. It is here full of unrecog-nizable Thamnastraaan corals (which appear to have been rolled), andabundance of Hemicidaru crenularis, Cidaris florigemma, ApiocrinusMoissyanus, Terebratula maltonensis, and Pecten vimineus. There isa thickness of about 120 feet, all made of similar material exceptnear the top, where about 16 feet is made of massive crinoidal lime-stone as near Verdun. This latter type, therefore, as there, is sub-ordinate to the Coral Bag; and we hence learn the age of the magni-ficent freestones of this character worked about seven miles to thesouth at Lerouville, where the quarries have a 100-foot face, all ofthe same material, with occasional Cidaris jlorigemma, Terebratulainsignis, and other fossils. We note also that, whereas near Yerdunthe coral-beds formed the capping to the crinoidal limestones, herethe latter lie at the top or nearly so, and no definite position in the. 512 J. F. BLAKE ON THE UPPER Coral Rag can be assigned to either of these forms. Above the CoralRag, on the road to St. Mihiel, are the more compact, almost litho-graphic limestones with Nerincece as before, occupying a wide expanseof country. So far, therefore, the Verdun form is fairly continued;but when we examine the exposures seen in other valleys an inter-esting modification is observed. The deeper sections on the rightbank of the Meuse show the base of the Coral Rag to be occupiedby far more oolitic and regularly-bedded stone than any seen atApremont; but on the left bank, quite close to St. Mihiel, a recent cut-ting gives a first real indication of something corresponding to our trueCoralline Oolite. At the base of this cutting is 8 feet of FerruginousOolite crammed with fossils—Ammonites convolutus ?, Pholadomyadecemcostata and P. deltoidea, Mytilus pectinatus, Perna quadrata,Pecten articulatus, Ostrea dilatata,
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Keywords: ., bookcentury1800, bookdecade1840, bookidquarte, booksubjectgeology
