130 Reports and Proceedings. 



similar to those at Chillesford, and under it the well-known bed of 

 mammaliferous or Norwich Crag, with the nsual shells. The author 

 also showed that in this cliff and the one nearer Lowestoft traces of 

 the Forest-bed clearly set in upon the Chillesford clay. He then 

 traced these beds at the base of Horton Clifl", and then passed on to 

 the well-known cliffs of Happisburgh and Mundesley. He consi- 

 dered 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, to which the author proposed the names of 

 " Southwold Sands and Shingle." These usually are very unfossi- 

 liferous, 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 

 Chillesford sands, as already shown by other Geologists, on the 

 evidence of the organic remains. Mr. Gwyn Jeffreys, who had care- 

 fully examined the shells of the Norwich Crag for the author, stated 

 that a considerable number of Arctic species were found in the 

 Norfolk Crag which did not occur 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 confirmed. 



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 Creensand 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 

 give the great features to the country. 



Discussion. — Mr. Gwyn Jeffreys observed that no littoral shells occur in the Coralline 

 Crag ; in the Eed Crag they abound. In the Norwich 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, exclusive 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 Corhicula fluminalis and Paludina unicolor. Twenty 

 species in the Norwich Crag have not been found in the Red or Coralline Crag, a,nd 

 he therefore thought there was some diiference in their geological age, the Norwich 

 Crag being both more recent than the Red Crag, and its shells of an Arctic or more 

 northern kind. Tellina balthica he regarded as significant of brackish-water condi- 

 tions. Actceon Nooe, a characteristic shell of the Red and Norwich Crag, had been 

 found fossil by Prof, Steenstrup in Iceland. 



