On the Geology of the Neighbourhood of Carmarthen

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Abstract
I. Introduction and Bibliography. The area described in this communication has Carmarthen for its centre, and lies approximately within a 4–mile radius of that town, as indicated in the accompanying sketch–map (Pl. XXV.). Our object in examining this district was to trace the continuation of the complex anticline which was discovered by the late Mr. T. Roberts, about 10 miles west of Carmarthen. In the map illustrating his paper the anticline is shown to be narrowing rapidly in the neighborhood of Mydrim, the Didymograptus –beds seem to wrap round the older Tetraptus series, and apparently the anticline is dying out. An examination of the beds round Carmarthen has enabled us to establish this conclusion, ans to show that in our own district we have a new anticline, the northern limb of which continues in the same direction as that of the anticline farther west, but with a core consisting of older rocks, which er correlate with the Tremadoc Slates. The southern limb of the new anticline is buried under Old Red Sandstone (which here encroaches farther north than at St. Clears), but in the northern limb we have a regularly ascending series from Tremadoc Slates to Dicranograptus –shales. To the east this regular succession of beds is disturbed by the presence of an extensive series of alternating grits and sandstones, with some shales, the last containing Bala fossils. The beds in question abut on those of Arenig age, but whether their appearance in this locality is due to faulting or to an

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