FOSSIL FAUNA. 119 



PLATE L. 



Encrinites and Pentacrinites. 



The Pear Encrinite of Bradford ; Mr. Pai'kinson. 

 {Apiocrinus rotundus, of Miller. 

 Parkinsoni, of Bronn.) 



The most generally known of the British Crinoidea, from its size, and abundance in one 

 particular locality, is the '•' Pear Encrinite " of Bradford in Wiltshire, some of the quarries 

 of the oolite on the heights above that picturesquely-situated town, yielding not only immense 

 quantities of detached plates and ossicula, but also numerous examples of the receptacle, 

 and occasionally the entire skeleton from the peduncle of the base to the extremities of the arms. 

 The lamented Mr. Channiug Pearce, and his father (now of Percy Place, Grosvenor, Bath), 

 when resident at Bradford, paid such unremitting attention to the collection of these fossils, 

 that perfect specimens were obtained, exhibiting the entire structure of the originals ; of these 

 some fine examples are preserved in the British Museum. Sir Charles Lyell mentions a very 

 interesting fact relating to the occurrence of these Crinoidea in the strata. He states that the 

 uj)per surface of a bed of limestone at Bradford is incrusted with a continuous pavement 

 formed by the stony roots of the Apiocrinites ; and upon this is a layer of clay in which are the 

 stems and bodies (receptacles) of innumerable examples ; some erect, others lying prostrate ; 

 while throughout the clay are scattered detached arms, stems, and receptacles. This submarine 

 forest of Crinoideans must therefore have flourished in the clear sea-water till invaded by 

 a current loaded with mud, which overwhelmed the living zoophytes, and entombed them 

 in the argillaceous deposit in which their remains are now imbedded.' 



The receptacle of this Apiocrinite is pyriform and very smooth, the plates are large and thin, 

 with radiating articulated surfaces ; the stem is short, smooth, and strong, the arms are simple, 

 and like those of the Marsupite ; the peduncle spreads out into an expanded base, which is firmly 

 attached to the rock ; sections of this part are generally of a purple colour. 



Fig. 1. Part of the column of the Bradford Encrinite. 2. Part of the receptacle; a minute 

 incrusting coral {Bryozoa) is attached to the lower part, giving the stem a rough 

 appearance. 



Figs. 3, & 4. Surface of detached plates of the receptacle. 



Fig. 5. Portion of the column partly covered with a cortical covering of a purple colour 

 possibly the original investing membrane. 



' See Wonders of Geology, vol. ii. p. 653. 



