Reviews — Prof. Lindstrom — Ascoceratidce and Lituitidce. 375 



the area, including also those, like the Chalk, Reading Beds and 

 London Clay, which were identified by Prof. Prestwich from evidence 

 obtained in a well-boring at Yarmouth. The cliffs exhibit the best 

 sections we have in England of the " Chalky Boulder Clay," but 

 the beds of most interest belong to the Forest Bed Series, and these 

 are exposed at intervals along the base of the cliffs, being usually 

 much obscured by talus. 



Some notes on borings made along this coast are contributed by 

 Mr. Clement Reid, and it is interesting to learn that traces of Crag 

 were found below the base of the cliff at Pakefield. It seems likely 

 also that some portion of the Crag Series is represented in the beds 

 (120 feet thick) grouped as "Recent Estuarine Deposits" in Prof. 

 Prestvvich's record of the deep well at Yarmouth ; but Mr. Blake 

 expresses no opinion on this subject. These Estuarine deposits are 

 surmounted by about fifty feet of Blown sand and shingle, on which 

 the town of Yarmouth stands. The town indeed is built on an old 

 sand-bank, which is supposed to have been isolated from the land 

 until about a.d. 1000. A representation of this " popular tradition " 

 is given in the Yarmouth Hutch Map, a copy of which was published 

 by S. Woodward (History of Norwich Castle, p. 48) ; and Mr. 

 Blake quotes Spelman, who says that this ground first became firm 

 and habitable about the year 1008. 



The Broads form a pleasing feature of the inland scenery. These, 

 according to Mr. Blake, in all probability date back to the times 

 when the main river-channels formed branches of an estuary. Tidal 

 action then assisted in scouring out these shallow basins, and they 

 were afterwards to some extent dammed up by bars that were formed 

 across the outlets of the valleys in which they lie. 



Appendices to this work include accounts of well-sections and 

 borings, lists of fossils from the Forest Bed Series and from the 

 Glacial Sands, and an account of the Lowestoft China, etc. 



III. — The Ascoceratidce and the Lituitidce of the Upper Silu- 

 rian Formation of Gotland. Described by G. Lindstrom. 

 40 pages and 7 plates. Communicated to the Royal Swedish 

 Academy of Sciences, 11th December, 1889. (Stockholm, 1890.) 1 

 CJO much of the work of the paleontologist of our day necessarily 

 O consists in revising that of his predecessors, that the appearance 

 of a palasontological memoir, written by a master of the craft, and 

 containing new facts and deductions, cannot fail to arouse more than 

 ordinary interest. After long and patient research, Dr. Lindstrom 

 has brought to light, from the rich Silurian deposits of Sweden, 

 nearly the whole of the missing parts of the shell of Ascoceras. 

 Though this discovery has been anticipated to some extent by the 

 author in a paper communicated to this Magazine (December, 1888), 

 we have in the present memoir a very complete and clear account 

 of the structure of Ascoceras, and an allied new genus (Choanoceras) 

 illustrated with a series of admirable plates, containing numerous 

 figures. 



1 "Written in English. 



