238 W.N. THAYER 
is generally satisfactorily delimited. It is separated from the 
Central Lowland for considerable distances by an eastward facing 
escarpment from 200 to 1,000 feet high. The most conspicuous 
AES 
= acs L/ = 
Sn OAV ke 
oS 
, Xs 
: oe SS 
LIL LT hie 
LE) LM at ; 
He aoe 
LLP 17 qottaee 
Cee \) m0 erat 
APL aes 
baaeae e 
CEREEERECE creer 
PHYSIOGRADHIC |} Poser 
*| DIVISIONS HH Baeee ae : 
NORTH AMERICA. is ars c 
ae ey |) 
portion of this escarpment (the Missouri coteau) begins near the 
southern boundary of North Dakota and extends northward to 
about the fifty-fourth parallel! Beyond this to the vicinity of 
* tC. A. Young, loc. cit. 
