564 Reviews — Geological Survey — Stoke-on-Trent. 



shales and grits belonging to the Pendleside Series are classed with 

 the Millstone Grit. Thus the new map indicates the absence of rocks 

 of the true Yoredale type and the Permian series in the Stoke-on- 

 Trent area. A dolerite dyke intrusive in Upper Coal-measures, and 

 Bunter Pebble-beds, are mapped for the first time. The maps, both 

 drift and solid, are accurate and full of detail, and we congratulate 

 Mr. W. Gibson and his colleagues on the result of their work. In 

 my copy of the solid map there is one small error of colour which 

 does not appear on the drift edition : the lower part of the band 

 representing Upper Coal-measure limestone south of Chesterton is 

 coloured bright blue, instead of being the same tint as the patch 

 a little to the north. 



The Memoir (pp. 1-87, with several diagrammatic illustrations) 

 might be included as a heading for the new section. It 

 appears to us to be carefully and thoughtfully written, sufficient 

 as an explanation of the map, and accurate in detail, the worst 

 faults being probably printer's errors. Due thanks are given for 

 all the local help received, and it has not been of small amount. 

 Owners and engineers of mines have generously placed their plans 

 and sections, and journals of borings, in the most unselfish way in the 

 hands of the Survey, and local geologists have received the com- 

 pliment of having many of their very radical views adopted, after 

 a most careful review of the evidence in the field. 



We note the absence of Permian and Yoredale beds from the 

 table of strata; instead of the Permian Mr. W. Gibson gives his 

 carefully worked out sequence of the Upper Coal-measures of North 

 Staffordshire, and we read in the preface that " The Pottery Coal- 

 field presents a type development of the Midland coalfields, to which 

 the sequence in other districts can be referred." 



Chapter ii, on the Millstone Grits and the beds below, by Mr. G. 

 Barrow, F.G.S., is headed by an instructive section of the rocks 

 across Endon. He remarks on the peculiar character of the black 

 shales below the Crowstones and the Stanley Grit. " The dark 

 shales contain a great number of small plant-remains, the mode of 

 occurrence of which is suggestive of leaves falling into comparatively 

 smooth or quiet waters. They further suggest the idea that much 

 of the shale may be due to a process of filtration of coarser material 

 by dense vegetation, which arrested the flow of the heavier sand 

 particles, and at the same time supplied the great number of 

 comparatively uninjured fragments of plants." This idea is full 

 of suggestion, but it connotes the nearness of land, and these 

 beds thin out very rapidly to the south and west. We note one 

 fault, almost characteristic of Survey Memoirs, in this chapter. 

 Mr. Barrow is quite contented with the generic names of his fossils, 

 but we wish he had recognized the great importance of adding th& 

 species also. Goniatites and Aviculopecten convey very little accurate 

 knowledge of horizons. The single important fact, however, comes- 

 out, that the shales between the grits and crowstones contain marine 

 fossils as a rule. We miss, too, the list of plants found when driving 

 through the shales between the first and third grits at Stocktort 



