BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 



Vol. 26, pp. 243-254 JUNE 28, 1915 



LENGTH AND CHARACTER OF THE EARLIEST INTER- 

 GLACIAL PERIOD ' 



BY A. P. COLEMAN 



{Read before tJie Society Decemher 30, P.J13) 



CONTENTS 



Page 



Introduotiou 24:) 



The Dou bed.s 244 



The Scarboro beds 247 



Difficulties of Professor Wrighfs iiiteiiiict.ition 248 



Interglacial deposits in other places 251 



Length of inter-Glacial time 252 



Inti.'odiction 



The earliest inter-Glacial period known in Canada is l!i:it of the To- 

 ronto formation, which has heen described more tliaii (Hicc. iind is some- 

 what well known to Pleistocejie geologists. K.\ca\alions nc;ii' Toronto 

 and elsewhere provide fresh information in I'cgard lo it fi-itni time to 

 time and give emphasis to the conclusions already reached as U) its length 

 and the charactei- ot its climate, and special studies of llic gciu'ral rela- 

 tionships have been made by the writer in connection with the recent 

 visit to Toronto oL' the Geological Congress. As there arc still some 

 |ii'oniiiicnt Pleistocene geologists who refuse to admit an iiiici'-Glaciai 

 inlerxal of gi-cat length and of mild climalr, it is ])roposi'(l to hi'iiig to- 

 gctluM' here the latest evidence of the reality and imporlaiiee of ibis iiiter- 

 Glaeial pei'iod. 



\\ Toronto li\c well de!iiie(! sheets o[" boiddei'-elav ai'c knoviii, willi 

 Tour sheets of interglacial stratilled sand and clay separating them, 

 'i'liese inlerghu'ial deposits vary from ■'."> to is,") j't'ei in tliickncss and 

 donbtless represent very dilTei-eiit interval^ (d' lime. In 1 wo of them 

 fossils have been obtained; but the lowest, ;ind iberefoi'e oldest of lliem 



MiiniiMcrlpI riTi'lvid liy llic .SiM-n-iar.v nf ilic Si)i'li'i> .\|iril '_', I'.Ml. 



