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 GEOLOGY the commercially important ' Whitehead Limestone,' and separated there- from by more dolomites is the equally, if not more, important ' Crease Limestone.' This latter is the chief repository of the iron-ore, which has been worked from time immemorial in the Forest district, as the numerous old workings, locally called ' scowles,' testify. Fossils are fairly common in the ' Crease Lime- stone,' and as the assemblage is similar to that of the Syringothyris Zone of the Bristol district, it is obvious that they must be on the same stratigraphical horizon. Fossiliferous limestones alternating with dolomites make up the deposits equivalent to the Zaphrentis and Cleistopora Zones of the Bristol district, and at their base are the beds which are characterized by the pelecypod Modiola lata and numerous ostracods. Apart from Dr. Vaughan few geologists have given attention to the Carboniferous rocks of Herefordshire. The Great Doward is capped with Lower Limestone Shales to which, farther to the south-east, succeeds the Mountain Limestone. From the Limestone, Symonds collected several brachiopods, such as Productus and Spirifer, and fish-remains — teeth and spines ; while the writer has procured from one of the actively-worked quarries a coral identified by Dr. Vaughan as Michelinia cf. favosa. It indicates the Zaphrentis Zone, and it is very interesting to note that while fish-remains occur here — for it was probably from these beds that Symonds obtained his specimens — precisely similar forms occur in the Zaphrentis Beds of the Avon section at Clifton, and in the Clee Hill area at Oreton. Associated with the limestone in the quarry from which the writer obtained the coral are some shale -beds with thin seams of very fine-grained grit, which on account of their having been crushed and used in the neighbourhood for cleaning pur- poses are called by the quarry-men ' Silver Sand.' The district between Hope Mansel and the Wye sadly requires re- mapping from a geological standpoint. At Howie Hill there is a small outlier of the basement-beds of the Lower Coal Measures, containing a few seams of coal that have been worked in the past ; and the locality is interest- ing because in ascending the hill a more or less complete succession of the beds from the Old Red Sandstone to the Coal Measures can be studied. The actual sections are not very good ; but Symonds collected a con- siderable number of fossils from them. The late H. D. Hoskold furnished the most detailed account of the geology of the Howie Hill district that has appeared,'' but its value is somewhat destroyed by the greater part being obviously based upon the existing geological maps, which — as has been remarked — require revision. Quarrying operations have been extensively carried on in the neigh- bourhood of Howie Hill and on the hill-top about a mile to the west of Mitcheldean. Most of the quarries are now abandoned, but from near Silverton Farm Mr. E, B. Wethered collected many fossils, principally from the Cleistopora Zone, and it was in this neighbourhood that Dr. Vaughan obtained the greater part of his information as to the local faunal and stratigraphical successions. Near here is the ' Deep Cutting,' which displays so well the transition from the Old Red into the Carboniferous System, "^ Proc. Cottestvold Nat. F.C. x, pt. ii for 1 890-1, pp. 142-4. I 25 4