THE SCIOTO I[LLINOIAN LOBE 489 
described in the present paper. This later and more leisurely field- 
study gives greater prominence and exactness to this curve of local 
lobation first examined by Leverett. 
In Licking County.—Save in the valleys, the Ilinoian drift near its 
front is so attenuated that mapping it is a problem of elimination, or 
the careful study of the rather maturely dissected divide areas. The 
lesser details of topography in the marginal zone appear to have had 
slight influence on the outline of the ice-front, while obviously exer- 
cising a considerable control over the duration of the ice in its position 
TOWNSHIPS 
4 Eden 
2Fallsburgh 
3.Mary Ann 
4 Perry 
5S Madison 
6 Hanover 
2franksin 
8 Hopewel/ 
9 Bowhng Green 
LICKING COUNTY, 0. 
L Licking Co 
aMuskingum Co 
os Hanover Dam 
L 
Border of Lllinoran Ice showing two 
valley dependencies. eel ee 
Fig.t Fig.2 
of maximum reach. This latter fact necessitates patient observa- 
tion, particularly where the stratigraphy did not encourage differen- 
tial-weathering effects previous to glaciation; it is evident that on 
slopes of heterogeneous rock structure facing the direction of ice- 
movement, benches of the more resistant formations, weathered into 
semi-detached spires and blocks,! would have suffered some from ice- 
work, even though the products of residual decay did not receive a 
noticeable admixture of glacial drift. But among the hills, where the 
rock structure is more uniform, and the weathered slopes correspond- 
ingly even, the absence of foreien material must be established before 
drawing ae drift-line; and in these higher areas an unexpected 
localization of erratics surrounded completely by territory in“which 
1 F. Carney, Bulletins of Denison University, Vol. XIII (1906), p. 124. 
