GREAT OOLITE ! FULLONIAN. 229 
Greensand at JNutfield in Surrey and 'Woburn in Bedfordshire, 
and beds or seams are found in places in the Ludlow Series, as 
well a? in other strata. Hence it has been suggested that the 
term "'Fuller's Earth -Oolite," be used to distinguish the beds of 
Jurassic age.* This name however is not satisfactory, for 
although it was given to notify the age of the beds, it might be 
taken to indicate their lithological character, whereas they exhibit 
no oolitic structure. Again, the occurrence in the formation of 
beds of economic fuller's earth is local. For these reasons some 
modification of the name appears desirable, and it is suggested 
that the term Fullonian (from the Latin Fullonius) would meet 
all requirements. The beds are to some extent equivalent to the 
Vesulian formation of Marcou, named from the town of Vesoul, in 
Haute-Saone. 
Where best developed, in Dorsetshire and Somersetshire, the 
Fuller's Earth or Fullonian formation has been divided as 
follows: 
Upper Fuller's Earth Clay. 
Puller's Earth Rock. 
Lower Fuller's Earth Clay. 
The clays are blue, grey, and yellowish in colour, and are 
usually more or less marly in character ; only the upper bed has 
yielded the fuller's earth of commerce. Nodules of "race," 
occasional bands of earthy limestone and thin layers of sandstone 
occur in the clays. 
The Fuller's Earth Rock which was recognized by William 
Smith (1815-16), consists of earthy limestone, hard enough in 
places to be used as material for mending roads, though it cannot 
be recommended for the purpose. A specimen from Oldford, 
Frome, examined under the microscope by Mr. Teall, showed 
organic fragments, and a few quartz grains, in a granular 
amorphous matrix. The bands of rock alternate with soft marls, 
and they are often nodular or impersistent in character. They 
have been traced northwards more or less persistently from 
Dorsetshire as far as Lansdown near Bath ; beyond this the rock- 
beds are less constant, and have only been recognized in places. 
The Fuller's Earth Rock is thus a lithological rather than a 
stratigraphical division, for the stony bands merge gradually into 
the clays above and below, and cannot be regarded as having a fixed 
horizon. Fossils, as a rule, are more abundant in the stone-beds 
and associated marls, than in the more clayey divisions, but the 
latter are especially characterized by Ostrea acuminata, and the 
economic fuller's earth has yielded a large number of Ostracoda.* 
On the whole, Lamellibranchiata and Brachiopoda are the 
most abundant fossils. The remains of Saurians and Fishes 
occur, but rarely. Cephalopoda are not uncommon in the Fuller's 
Earth Rock, and it is characterized by the presence of Ammonites 
* T. R. Jones and C. D. Sherborn, Proc. Bath Nat. Hist. Club, Tol. vi. p. 249. 
