754 C. CALLAWAY ON THE QUARTZTTES OF SHROPSHIRE. 



42. On the Quartzites of Shropshire. By Charles Callaway, 

 M.A., D.Sc. Lond., F.G.S. (Read June 5, 1878.) 



Contents. 

 Introduction. 



A. Wrekin — Church-Stretton area. 



1. General Description. 



a. Wrekin subarea. 



b. Caer-Caradoc subarea. 



c. Cardington-subarea. 



2. Relations to the associated rocks. 



3. Age. 



4. Fauna. 



B. Stiper-Stones area. 



Introduction. 



The geology of South Shropshire, though it has received considerable 

 attention from geologists, has been seriously misunderstood. This 

 is owing partly to the disturbing influence of great south-west faults, 

 partly to the obliterating influence of metamorphism, and partly to 

 mistaken views of the causes of metamorphism. 



In attempting to unravel the complexities of this disturbed area, 

 I have arrived at some definite results, the first of which I commu- 

 nicated to this Society in a paper entitled, " On a new Area of Upper 

 Cambrian Rocks in South Shropshire, with a description of a new 

 Fauna " (See vol. xxxiii. p. 652, of the Quarterly Journal of the 

 Society). In that paper I showed that a part of the so-called 

 Lower Caradoc rocks south of the Wrekin were of the age of the 

 Dictyonema-sh&les of Malvern and Pedwardine, and that a part of the 

 so-called " quartzite " of the Wrekin consisted of Hollybush Sand- 

 stone. I deferred discussion on the true quartzites and on the 

 igneous rocks of the district. The latter I hope to be able to prove 

 in a future paper are only to a slight degree disruptive, and mainly 

 consist of a great bedded* series of lavas and tuffs of Precambrian 

 age. My second instalment of information is the announcement that 

 the so-called Caradoc quartzites of the Wrekin and Church-Stretton 

 area are of Cambrian or Precambrian age. In this connexion I 

 shall notice the quartzites of the Stiper Stones, so as to include, so 

 far as I know, all the quartzites of Shropshire. 



A. Wrekin — Church-Stretton Area. 



1. General Description. 



a. Wrekin subarea. — This district contains by far the largest 



* The discovery of the bedded character of these rocks was made indepen- 

 dently by Mr. S. Allport soon after myself, and was announced by him to this 

 Society in May 1877, when he read a most valuable paper on their microscopic 

 structure and composition. 



