Supercretaceous formations. 517 



Miocene, although belonging to a more remote part of that period 

 than the Red Crag. Having obtained from M. Dujardin a collection 

 of 240 shells from the Faluns of Touraine, he found with Mr. George 

 Sowerby's assistance that the recent shells were in the proportion of 

 twenty-six per cent., so that he has now come round to the opinion 

 long ago announced by M. Desnoyers, that upon the whole the Crag 

 of Suffolk corresponds in age with the Faluns of Touraine, both be- 

 ing Miocene, although the species in the two countries are almost 

 entirely distinct, those of England having a northern and those of 

 France a sub-tropical character. I am also informed by Mr. Lyell, 

 that out of 400 marine and freshwater species, from the Eocene strata 

 of the London and Hampshire basins, Mr. G. Sowerby was scarcely 

 able to identify two per cent, with living shells. It is satisfactory 

 therefore to observe that the test of age derived from the relative 

 approach to the recent Fauna is in perfect accordance with the in- 

 dependent evidence drawn from superposition. We ascertain for 

 example by superposition that the freshwater strata of the mud cliffs 

 of East Norfolk rest on Norwich crag, and are the newest forma- 

 tion of all. They are then followed in the descending series by, 1st, 

 the Norwich, 2ndly, the Red, and Srdly, the Coralline Crag, beneath 

 which is the London Clay. The same order of sequence is indi- 

 cated by the organic remains considered independently, and simply 

 with reference to the degree of their correspondence with the ex- 

 isting Fauna. 



It has been known for many years, that near Bridlington, in York- 

 shire, sand and clay containing marine tertiary shells had been ex- 

 posed on the coast. From an examination of the shells collected 

 there by Mr. Bean, Mr. Lyell finds the deposit to agree in age with 

 the Norwich Crag. 



I cannot conclude these remarks without observing, that some 

 part of the confusion and apparent inconsistency of the opinions of 

 different conchologists, respecting the age of the Crag, must have 

 arisen from the intermixture of fossils derived equally from 

 the Norfolk and Suffolk beds, or from strata, some of which now 

 turn out to be referable to the Older Pliocene, others to the Miocene 

 period. 



From an examination of some fossil shells, identical with recent 

 species collected by Capt. Bayfield from the most modern deposit 

 near the Gulf of St. Lawrence, and near Quebec, Mr. Lyell infers, 

 that the climate of Canada was colder than now during the era im- 

 mediately antecedent to our own times. The shells, which were de- 

 termined by Dr. Beck, differ in great part from those now living 

 in the Gulf of St. Lawrence, agree more nearly with arctic genera 

 and species, and resemble those which Mr. Lyell collected at Udde- 

 valla, in Sweden ; whereas, if the living shells most abundant in the 

 Swedish and Canadian seas are contrasted, they differ almost en- 

 tirely. From notes sent by Capt. Bayfield, it appears that at 

 different depths in the stratified sand and clay containing the 

 fossil shells, near Quebec, insulated boulders are numerous, which, 

 it is presumed, have been brought down at distant intervals by 



