282 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. (Jan. 26, 
burgh and Mundesley. He considered the Chillesford clay to pass 
beneath the Elephant bed, and to represent some part of the Forest- 
bed. The same clay may be traced to near Weybourne. The Crag 
under these beds he referred to the Chillesford sands. Mention was 
then made of the sands and shingle above the Chillesford, for 
which the author proposed the names of “ Southwold Sands and 
Shingle.” These usually are very unfossiliferous; but at two or 
three places near Southwold the author found indications of an 
abundance of shells (Mytilus &c.) and Foraminifera in some iron- 
sandstones intercalated in this series. In the Norfolk cliffs these 
beds contain alternating seams of marine and freshwater shells. 
The inland range of the beds to Aldeby, Norwich, and Coltishall 
was next traced, and the Chillesford clay shown to be present in 
each section, and the sands beneath to be referable to the Chilles- 
ford sands, as already shown by other geologists, on the evidence of 
the organic remains. Mr. Gwyn Jeffreys, who had carefully examined 
the shells of the Norwich Crag for the author, stated that a consi- 
derable number of arctic species were found in the Norfolk Crag 
which did not oceur in Suffolk. While, therefore, the Norwich Crag 
seems to be synchronous with a portion of the Suffolk Crag, that 
portion is the upper division ; and therefore the triple arrangement 
proposed by Mr. Charlesworth and advocated by Sir C. Lyell, together 
with the fact of the setting in of a gradually more severe climate, 
pointed out by the late Dr. Woodward and by Sir C. Lyell, are con- 
firmed. 
Mr. Prestwich then referred to the origin of the materials of the 
Southwold shingle, and showed that, with few exceptions, they 
came from the south. In it he had found a considerable number of 
worn fragments of chert and ragstone from the Lower Greensand of 
Kent. He considered this a convenient base-line for the Quaternary 
period, as then commenced the spread of the marine gravels over the 
south of England, and soon after commenced the great denudations 
which have given the great features to the country. 
Discussion. 
Mr. Gwyn JEFFRreYs observed that no littoral shells occur in the 
Coralline Crag, while in the Red Crag they abound. In the Nor- 
wich Crag there is also evidence of littoral conditions, but in certain 
places the shells exhibit a deep-water character. In the Norwich 
Crag, after eliminating as derivative or extraneous certain species 
(as had already been done by the late Dr. Woodward), he finds, ex- 
clusive of varieties, 140 species, of which 123 are living, and 17 are 
supposed to be extinct. Of these 123, 101 still live in the British 
Seas, 12 are arctic and North American, 8 Mediterranean, and 2 
Asiatic. The southern species were probably derived from the 
Coralline Crag. The two Asiatic species were the Corbicula flumi- 
nalis and Paludina unicolor. Twenty species in the Norwich Crag 
have not been found in the Red or Coralline Crag; and he therefore 
thought there was some difference in their geological age, the Nor- 
