266 Wisconsin Academy of Sciences, Arts and Letters. 
are substantially as follows: At a\ the limestone debris, as 
displayed along the Madison horizon is quite abundant, con¬ 
tinuing so perhaps two-thirds of the distance to b. It then 
begins to diminish in abundance, quite rapidly toward the end, 
The contour lines indicate intervals of about 50' 
The dotted belt a. is the horizon at the Madison beds and by the 
frequency of the dots I have endeavored to convey an idea of the rela¬ 
tive abundance of limestone debris along that horizon. The portion 
above the dotted belt is the Lower Magnesian cap. 
The deposit c. d. is interrupted for a space above d, apparently 
covered by Loess. At d. the deposit forms a double ridge, with an in¬ 
terval of a rod or two between. 
Below d. the deposit has been removed by the forming of a new rock 
gorge, the old valley axis to the westward being closed. The character 
of the filling is not well shown. Such newly cut channels are not un¬ 
common, and are not necessarily due to the closing of an old channel 
by morainic deposits. 
and is wanting for a considerable space near b (about 30' in 
this case but much more in other cases). Outside of b toward o 
we reach the upper end of the deposit c resting on sandstone 
waste and rising abruptly, and steeply to a hight of six feet* 
