EOCKS OF THE ATLANTIC COAST OF CANADA, ETC. 815 



part specifically identical with those of England (Windsor Series 

 of recent papers). 



3. A Millstone-grit series consisting of coarse sandstones and 

 shales with conglomerate, mostly of red colours. 



4. The Main or Productive Coal-measures, precisely similar in 

 character to those of Britain. Of 1 35 species of fossil plants which 

 I have catalogued from these beds more than one half are specifically 

 identical with those of Engiaud. The animal fossils of these beds, 

 Batrachians, Eishes, Crustaceans, and Mollusks, are also akin to those 

 of England. In the class of Batrachians a still more close aj)proxi- 

 mation appears in those obtained by Eritzsch in the Upper Car- 

 boniferous of Bohemia. 



5. A Permo-Carboniferous series, perhaps corresponding in age to 

 the Lower Permian of England, and consisting largely of Bed Sand- 

 stones with species of plants characteristic in Europe of the Lower 

 Permian, but including no limestones. 



The conditions of the Carboniferous are on the whole similar 

 throughout jS'orth America, except in the extreme West and locally 

 in the Appalachian region : but in Nova Scotia, Newfoundland, and 

 New Brunswick they are more nearly allied to the British type, 

 except in the abundance of red marls and gypsum in the Lower part. 



Interstratified trappean rocks, similar to those in Scotland and 

 England, occur in Nova Scotia and New Brunswick, especially in the 

 Lower Carboniferous. 



The details of the Carboniferous and Permian of Nova Scotia and 

 Prince Edward Island are so fully given in the papers referred to 

 in the notes, that the above general mention will be sufficient here. 



One fact of general application which is admirably illustrated in 

 the Carboniferous of Nova Scotia is the extreme sensitiveness of the 

 earth's crust to unequal pressure. The Coal-formation of the Cum- 

 berland district, 50u0 feet in thickness, and consisting wholly of 

 beds which must have been deposited almost exactly at the sea-level, 

 shows that for every inch of sediment or of vegetable matter there 

 must have been a corresponding depression of the crust. This 

 accurate correspondence of sedimentation with subsidence has long 

 appeared to me one of the most striking facts in geological dynamics. 



The Triassic Bed Sandstone of Nova Scotia and Prince Edward 

 Island and the associated Traps closely resemble the same for- 

 mations in England. Like them they contain no important marine 

 limestones, and their fossils are limited thus far to a single Dino- 

 saurian reptile and a few fossil plants. In these it is far inferior 

 to deposits of the same age further to the south on the Atlantic coast 

 of the United States. In America, as in Europe, the Triassic flora 

 and land- and freshwater-faunas seem to have been of southern 

 origin. 



The maritime region of Eastern Canada is remarkable for its 

 deficiency of Mesozoic rocks newer than the Trias. If there are 

 such deposits, they must be, like the Cretaceous rocks believed to 

 exist further south on George's Banks, still under the sea. It is only 

 on Greenland and the Arctic Islands that we find beds rangirg from 



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