Reviews—Geology in the Field. 429 
Yoredale Series, of Postdonomya Becher’, which is characteristic else- 
where of the Pendleside Group. The Permian beds are then dealt 
with, and it is noted that the Magnesian Limestone is succeeded 
conformably by ‘Triassic red sandstones and marls—beds which, 
curiously enough, have been regarded as Keuper by some authorities. 
The important sills and dykes of post-Carboniferous date and the 
Glacial and newer deposits finally receive attention. 
The second article is on ‘‘ The Malvern and Abberley Hills, and the 
Ledbury District’, by Professor T. T. Groom, who gives a summary 
of his detailed researches on the tectonic structure of the region, 
together with concise accounts of the Archean and the fossiliferous 
Cambrian, Ordovician, and Silurian rocks. Special attention is given 
to the subdivisions of the Silurian, and a valuable list of fossils, showing 
the range of the species from the May Hill Sandstone to the Upper 
Ludlow, is appended. 
‘‘ Shropshire” forms the subject of the third article, and is happily 
dealt with by Professor Lapworth. Brief accounts are given of the 
several types of pre-Cambrian rocks, the Rushton schists, the 
granitic and gneissose rocks, the Uriconian, and Longmyndian. It is 
remarked that the term Uriconian has been applied to certain dis- 
connected groups of ashes and lavas, and in a table showing the 
apparent descending sequence of the lithological groups in Uriconian 
and Longmyndian the author has been led to place at the top the 
Linley volcanic series, equivalent to the Western Uriconian of 
Callaway, and at the base the Cardington volcanic series or Eastern 
Uriconian of Callaway. The intermediate groups of Western and 
Eastern Longmyndian are ranged under eight subdivisions. This 
classification, based on Professor Lapworth’s detailed field-researches, 
will be of immense service to future workers. The Cambrian rocks 
are briefly described, and the various local divisions established by 
the author in the Ordovician system again give information of special 
importance. Then follow accounts of the Silurian divisions, and 
brief descriptions of Carboniferous and newer formations, of tectonic 
geology and physiography. 
The fourth article, on ‘‘ Charnwood Forest”’, is naturally written by 
Professor W. W. Watts, whose elucidation of the complex structure 
and of the nature of the buried mountain mass has been a great 
achievement. Preserved beneath a cover of Keuper Marl, the erosion 
of this newer deposit has revealed portions of what the author terms 
“the fossil Triassic landscape of Charnwood’’. 
In the fifth article Mr. W. G. Fearnsides gives an account of the 
main features in the geology of ‘‘ North and Central Wales”. Rocks 
from pre-Cambrian to the Old Red Sandstone, sedimentary, volcanic, 
and intrusive, are duly described, attention being given to the 
prominent and characteristic fossils and to the method of formation 
of the strata. It is noted that the Old Red Sandstone is locally 
continuous in all respects with the Downtonian. The author then 
discusses the general structure of the area and the various great earth- 
movements that have taken place, and in a series of diagrammatic 
sections he illustrates his views on the more important stages in the 
building of Wales from the Uriconian era to the present day. 
