§ 15. THE COTTESWOLD HILLS. 005 



The Bradford Clay. — In the neighbourhood of Brad- 

 ford, in Wiltshire, a subordinate bed of the forest marble 

 or blue limestone of the Great Oolite, is remarkable for 

 the abundance of the remains of a particular species of 

 crinoidean, called the Pear-e?icrinite of Bradford (Medals, 

 p. 318), which in some places occur under circumstances 

 apparently indicating that the animals still occupy the spots 

 where they grew. The clay is spread over the surface of a 

 stratum of limestone, and many of the Stone-lilies are 

 upright, with their root-like base attached to the calcareous 

 rock. " In this case," observes Mr. Lyell, " it appears 

 that the upper surface of the Great Oolite had supported for 

 a time a thick submarine forest of these beautiful zoophytes, 

 until the clear and still water was inyaded by a current 

 charged with mud, which threw down most of the stone- 

 lilies, and broke their stems short off near the point of 

 attachment. The stumps still remain in their original 

 positions ; but the numerous articulations once composing 

 the stems, arms, and body of the zoophytes, were scattered 

 at random through the argillaceous deposit, in which some 

 of them now lie prostrate."* 



15. The Cotteswold Hills. — As the elevated tract of 

 country called the Cotteswold hills, which extends for 

 thirty miles through the county of Gloucester, in a N.E. and 

 S. W. direction, having an average breadth of ten or twelve 

 miles, exhibits the principal characters of the English Oolites, 

 the following brief description will convey a general idea of 

 the physical geography and lithological structure of a 

 district composed of these deposits, f 



" The surface of this district has a general inclination to the S.E. 

 its eastern borders having an elevation of about 400 to 500 feet above 



* Elements of Geology, 2d Edit. vol. ii. p. 45. 

 f I am favoured with this account by Professor Woodward, of the 

 Agricultural College of Cirencester. 



