THE PEORIAN SOIL AND WEA THERED ZONE 249 



The extent of deglaciation suggested by these beds, so far 

 as space is concerned, can scarcely be supposed to have been 

 exceeded either by the Sangamon or the Yarmouth stage of 

 deglaciation. The Toronto beds constitute probably the most 

 decisive evidence yet brought forward in support of an exten- 

 sive deglaciation within the glacial period. The time involved 

 may reasonably be supposed to involve a portion of the glacial 

 period by no means small. Its rank should be as high as that 

 of any of the interglacial stages, even if less prolonged than 

 some of the earlier stages of deglaciation. Should it be proved 

 to represent the interval between the Iowan and Wisconsin 

 deposits, as now seems probable, the evidences above cited, from 

 the peripheral portion, may aid in determining its length, 

 namely, the leaching and erosion of the Peorian stage. As yet 

 the fauna and flora buried beneath the peripheral portion of the 

 Wisconsin drift have received little or no attention. Possibly 

 by the aid of this line of study the question of correlation may 

 be settled. 



Frank Leverett. 



