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 GEOLOGY (O/enus) scarabceoides and Agnostus pisiformis. In the higher (grey) shales, on the borders of Chase End Hill, the Rev. W. S. Symonds first found the characteristic ' hydroid zoophyte ' Dictyonema. Prof. Lapworth in referring to the numerous intercalated igneous rocks which occur both in the Hollybush Sandstone and Malvern Shales remarks that the majority are certainly intrusive.^ Prof Groom remarks that they include basalts and ophitic diabases, and were probably in- truded in Ordovician times. Much of the ground occupied by these Cambrian rocks is pasture land. The famous quartzite of the Lower Lickey, described in 1821 by Buckland, is well seen at Bilberry Hill, and further north at Rubery, where it is flanked by May Hill Sandstone. It has been compared with the quartzite of Hartshill, near Nuneaton, and like that rock it is extensively used for road-metal. According to Prof Lapworth, how- ever, the Lickey quartzite represents only the lower and middle portions of the Hartshill rock, the upper portion not being recognized at Lickey, although represented at Malvern by the Hollybush Sandstone. The only traces of fossils found in the Lickey rock are worm-burrows. The sequence of events at Lickey, according to the observations of Mr. W. Gibson, indicates that after the volcanic era of the Barnt Green rocks, a long period may have intervened before the laying down of the quartzite, SILURIAN Among the fossiliferous strata of Worcestershire none have proved more attractive than the Silurian, whether at Malvern or Dudley. The collections formed by the late Dr. R. B. Grindrod (of Townshend House, Malvern), and by the late John Gray (of Hagley), were remark- ably rich, and many other important sets of fossils have been gathered together. The rocks appear in broken anticlinal ridges at the Lickey Hills and Dudley, and again along the Malvern and Abberley ranges, but they do not occupy a large superficial area in the county. A great break separates them from the Cambrian, for we have no representatives in place of any of the Ordovician (or Lower Silurian) strata. The oldest subdivision known as the May Hill (or Upper Llan- dovery) Sandstone consists at Malvern of purple and grey grits and brown sandstones, some of them calcareous, some pebbly. Evidently a shore deposit, the May Hill Sandstone appears to rest indifferently on the older rocks whether Archaean or Cambrian, but we have to be cautious as Prof Groom remarks in distinguishing between the normal overspread of the newer formation, and the displacements due to sub- sequent earth-movements. Among the fossils of the May Hill Sandstone are Pentamerus 7
 * Proc. Geol. Assoc, vol. xv. p. 338 ; Groom, Rep. Brit. Assoc, 1 900.