CHAP. XI.] HANTONIAN PERIOD. 215 



to depths of 1,300 and 1,500 fathoms (9,000 feet), as if its 

 edge had for a long time formed the coast-line of western 

 Europe. 



Whether the west-European plateau was first upraised 

 in Eocene or in Trias sic time must remain doubtful, but 

 it is highly probable that the coast-line of the Eocene 

 land lay along the slope of this plateau, and that the 

 land then stood at a much higher relative level than it 

 does now; that is to say, the horizon of the Eocene 

 Atlantic cut the Eocene land at a level which is now 

 at least six hundred, and possibly several thousand feet 

 below the present sea-level. This high relative level 

 seems to have been maintained throughout the whole 

 period, and it is possible that the western and north- 

 western districts hardly participated in the oscillatory 

 movements which took place in the eastern areas of sedi- 

 mentation, but, being continuously exposed to detrition, 

 underwent more or less continuous elevation throughout 

 the whole period. There is no doubt that these districts 

 were at this time subjected to an immense amount of 

 erosion and detrition, and though denudation can hardly 

 be the primary cause of elevation, it is certainly calcu- 

 lated to accelerate it by removing material and thus 

 diminishing the weight to be lifted. Such a connection 

 between denudation and elevation has been pointed out 

 by several writers, notably Dr. Ch. Eicketts 1 and Capt. 

 C. E. Dutton. 2 



The similarity between the Lower Eocene floras of Ire- 

 land, Scotland, Iceland, and Greenland is so great, and 

 the climate which they indicate is so temperate, as to 

 make it highly probable that these four countries formed 

 at this time a continuous tract of land. There is still a 

 submarine ridge connecting Scotland and Greenland over 



1 " Geol. Mag.," 1883, p. 10. 



2 " Nature/' 1879, vol. xix. p. 251. 



