342 
ELEMENTS OF GEOLOGY. 
of echini, and other signs of a neighboring beach, are ob¬ 
served.* 
Great (or Bath) Oolite. — Although the name of coral rag 
has been appropriated, as we have seen, to a member of the 
Middle Oolite before described, some portions of the Lower 
Oolite are equally entitled in many places to be called coral¬ 
line limestones. Thus the Great Oolite near Bath contains 
various corals, among which the Eunomia radiata (Fig. 329) 
is very conspicuous, single individuals forming masses sev- 
Fig. 329. 
Eunomia radiata^ Lamouroux. {Calamophyllia, Milne Edw.) 
a. Section transverse to the tubes. 6. Vertical section, showing the radiation of the 
tubes, c. Portion of interior of tubes magnified, showing striated surface. 
eral feet in diameten; and having probably required, like the 
large existing brain-coral {Meandrind) of the tropics, many 
centuries before their growth was completed. 
.Different species of crinoids, or stone-lilies, are also com¬ 
mon in the same rocks with corals; and, like them, must 
have enjoyed a firm bottom, where their base of attachment 
remained undisturbed for years (c. Fig. 330). Such fossils, 
therefore, are almost confined to the limestones; but an ex¬ 
ception occurs at Bradford, near Bath, where they are en¬ 
veloped in clay sometimes 60 feet thick. In this case, how¬ 
ever, it appears that the solid 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 invaded by a current charged with mud, which threw 
down the stone-lilies, and broke most of their stems short off 
near the point of attachment. The stumps still remain in 
their original position; but the numerous articulations, once 
composing the stem, arms, and body of the encrinite, were 
scattered at random through the argillaceous deposit in 
which some now lie prostrate. These appearances are rep¬ 
resented in the section Fig. 330, where the darker strata 
represent the Bradford clay, which is however a formation 
* P. Scrope, Proc. Geol. Soc., March, 1831. 
