Ch. XX.] 



BRADFORD EXCRIXITEB. 



403 



tered at random through, the argillaceous deposit in which some now 

 lie prostrate. These appearances are represented in the section b, fig. 

 402, where the darker strata represent the Bradford clay, which some 



Fiar. 402. 



Apiocrinites rotundus, or Pear Encrinite ; Miller. Fossil at Bradford, Wilts. 



a. Stem of Aplocrinites, and one of the articulations, natural size. 



b. Section at Bradford of Great Oolite and overlying clay, containing the fossil encrinites. See 



text. 



c. Three perfect individuals of Apiocrinites, represented as they grew on the surface of the 



Great Oolite. 



d. Body of the Apiocrinites rotundus. 



geologists class with the Forest Marble, others with the Great Oolite. 

 The upper surface of the calcareous stone below is completely en- 

 crusted over with a continuous pavement, formed by the stony roots 

 or attachments of the Crinoidea ; and besides this evidence of the 

 length of time they had lived on the spot, we find great numbers of 

 single joints, or circular plates of the stem and body of the encrinite, 

 covered over with serpulce. Now these serpulce could only have 



Fig, 403. 



a. Single plate or articulation of an Encrinite overgrown -with serpuloz and bryozoa. Natural 



size. Bradford clay. 

 ~b. Portion of the same magnified, showing the bryozoan Biastopora diluviana covering one 



of the serpulcs. 



begun to grow after the death of some of the stone-lilies, parts of 

 whose skeletons had been strewed over the floor of the ocean before 

 the irruption of argillaceous mud. In some instances we find that, 



