FOEAMINIFERA IN THE DRIFT 47 



my criticisms will be readily accepted, yet they may possibly 

 help in clearing up some points which hitherto could not be 

 satisfactorily elucidated by other methods. The vast drift 

 deposits which shroud the country like a great mantle of clay, 

 sand and stones, frequently contain the remains of the ex- 

 clusively marine group of foraminifera. Mr. Joseph Wright, 

 a well-known European authority, has shown that the species 

 of foraminifera have a very wfde distribution in European 

 boulder-clays. And it appears, on the authority of Sir Henry 

 Howorth,* that Mr. Wright has likewise identified foramini- 

 fera. from American glacial clays. Samples were submitted 

 to him by the late Dr. G. Dawson from Saskatchewan 

 Eiver, 1,850 feet above sea-level, from Selkirk in Manitoba, 

 and from Ottawa. The sample from Saskatchewan contained 

 specimens of foraminifera referable to recent species, one 

 of which (Nonionina depressula) is also common in European 

 boulder-clays. 



It is quite possible that foraminifera may be found in many 

 other localities in the same clays ; indeed. Sir Henry Howorth 

 mentions that Sir William Dawson had found them generally 

 diffused in the Pleistocene clays of Canada. This fact, there- 

 fore, tends to support Colonel Peilden's f contention that all 

 the glacial deposits which he had examined in Arctic and Polar 

 lands, with the exception of terminal moraines now forming 

 above sea-level, are glacio-marine beds. - 



Supposing the waters of the Arctic Ocean had risen, per- 

 haps in consequence of the closing of the Atlantic Ocean, 

 and had poured into Hudson Bay, overflowing its banks, 

 and had then crossed the low-lying watershed separating 

 this northern region from the depressions of the Great Lakes, 

 the latter would soon have been filled with brackish water, 

 killing or driving away many of those forms of life that were 

 unable to adapt themselves to this change of conditions. 1 

 presume, of course, that troughs, not necessarily like the 

 lakes now existing, already occupied the same region in pre- 

 Glacial times. Such an hypothesis of this area having been 

 invaded by the sea in Pleistocene times is supported by some 



* Howorth, H. H., "Ice or Water," Vol. II., p. 216. 



t Feilden, H. W., " Glacial Geology of Arctic Europe," p. 57. 



