382 
LOWER OOLITIC ROCKS OF ENGLAND : 
Prof. Judd remarks that, " The marine shells of the series 
appear to be identical with those of the Great Oolite Lime- 
stones above, into which formation the beds we are describing 
insensibly merge." 
The freshwater fossils are for the most part too badly preserved 
for specific determination ; but much useful work might be done 
by geologists living in the district, in collecting and studying 
additional specimens. The only fresh-water species identified, is 
Cyrena Cunninghami. None of the plant-remains, so far as I am 
aware, have been determined. The " rootlets " occur at different 
horizons, and do not in themselves mark any important break. 
The following list will show the character of the fauna of the 
Upper Estuarine Series ; it is given mainly on the authority of 
Samuel Sharp.* 
LIST OF FOSSILS FROM THE UPPER ESTUARINE BEDS. 
Teleosaurus. 
Cerithium. 
Natica pyramidata. 
Paludina. 
Area rugosa. 
Astarte. 
Avicula. 
Cardium Strickland!. 
subtrigonum. 
Cucullsea concinna. 
Cypricardia bathonica. 
caudata. 
Cyprina loweaiia. 
Cyrena Cunninghami. 
Gresslya. 
Lima. 
Modiola gibbosa. 
Modiola imbricata. 
Lonsdalei. 
Nesera Ibbetsoni. 
Ostrea Sowerbyi. 
Pecten. 
Pinna. 
Pholadomya acuticosta. 
Tancredia angulata. 
axiniformis. 
planata. 
Thracia. 
Unicardiuni gibbosum. 
impressum. 
Unio. 
Rhynchonella coucinna. 
Eryma (allied to) elegans. 
Acrosalenia. 
GREAT OOLITE LIMESTONE. 
This division, which was so named by Prof. Judd to dis- 
tinguish it from other local members of the Great Oolite Series, 
consists of grey, white, and sometimes pinkish limestone, with 
bands of marl, yielding Ostrea Soivcrbyi, and O. subrugulosa. 
Prof. Judd remarks that, " Sometimes the limestones con- 
sist of comminuted shells and then split up into thin flags like 
the Forest Marble of the South of England, for Avhich they have 
been mistaken. Beds of this character are seen at Castor, 
Alwalton, &c. More usually the limestones are soft, white, and 
marly, abounding in casts of shells, those of the Myadce being 
especially abundant." 
Layers of rock that resemble the Forest Marble occur also at 
a higher horizon in the Great Oolite Clay. 
" The limestones at the bottom of the series sometimes attain to 
a considerable thickness, and very occasionally, as near Brigstock 
and Stanion, exhibit traces of oolitic grains ; but, as a general 
* Quart. Journ. Geol. Soc., vol. xxix. p, 263. 
