IMfVSlCAL AM) CMMA'I'AL COXDriTOXS. 7,-, 



Ai this jicridd the viillcy of llic Si. I^iiwiviice and the 

 onsteni coast, us far wost as lake ('liaiiii)laiii and tlu! east 

 end ((!' lake: Ontario, as well as the Itorders of the arctic 

 I)asiii and of the Tacilic, were under the waters of the 

 ocean and inlial»ited ]>y a licli lioical fauna, nearly all the 

 species of which, in its eastern developuu'iit, I have 

 myself dredj^'cd alive in the wateisof the estuary of the 

 St. Lawrence. On the other hand, the western i)lains 

 were covered with waters which have not affordcil marine 

 ainnials in their de])osits, hut hold remains of laud ])lauts. 

 Farther, these land ])lants were of species not arctic, hut 

 merely horeal or north temperate,* whiK' the proper 

 arctic llora nnist have heen still farther north. 



(.')) This nud-,i>lacial period was followed hy the second 

 houlder-dejjosit, in which still farther suhsideuce occurred, 

 and houlders were carried l)y tloatiu<i' ice to the sumnut 

 of the hi^i^her hills in eastern Canada and New Eu^'land, 

 up to the heio-ht of 4,200 feet, and in the llocky ^Jouu- 

 tains even to the great elevation of 5,289 feet.f This 

 second period of houlder-drift and its deposits must not 

 be confounded with the earlier till. 



(4) From this depression the continent arose <>radually 

 or by intermittent throes, leaving- the terraces of the hills 

 and the sand and gravel beds (Saxicava sand) of the 

 plains as evidences of the recession of the waters. This 

 elevation proceeded so far as to inaugurate the second 

 conthiental period, when the land was more extensive 

 than at present, and a southern fauna penetrateil far 

 north along our coasts, while great mammals, now extinct, 

 overspread the land. Since that time there have been 



* See Chapter V. 



t G. M, Dawson, Report on Superficial Deposit, Bow river, 1884. 



