256 Proceedings of Indiana Academy of Science. 
wider in the vicinity of Fairfax than it is for several miles either above 
or below this locality. No terraces flank the south side of the valley 
here, but on the inside of the great valley-bend more than the usual amount 
of terrace material is present. This abrupt turn of the valley certainly 
favored lateral planation on the outside of the great bend. The extra- 
ordinary concave bluff-line, with its farthest south extension near Phillips 
School, is a rather striking indication of the concentration of waters against 
the south side of the yalley. 
Another feature which enters into the problem is the fact that there 
has been much more water flowing in Salt Creek valley at times during 
the past than there is at present. Salt Creek is a small sluggish stream 
meandering in a valley rather too large for it. The Pleistocene valley-fill 
material and the flanking terraces.are proof that the valley once was a 
sluice-way for the exit of glacial waters. No doubt during the melting 
seasons of the glacial ice near the headwaters of this valley, the valley was 
in a highly flooded condition, and the stream that occupied it was much 
larger than the present one. Lateral planation must have taken place on a 
much greater scale during this time than at present. The much larger 
Pleistocene stream must have brushed all outside turns of the meandering 
valley with considerable vigor. The great curve cut out in the south bluff 
south of Fairfax must have been made during this time, as the curve 
seems unusually large to have been made by the present rather feeble 
stream. The present position of the stream channel has no relation to this 
great curve. In one or two meanders in the flood-plain the present stream 
does come against the south bluff in the northern part of section 36, but 
this touching of the bluff in these two places has not yet destroyed the 
symmetry of the great curve in the wall-like bluff. 
There is a strong probability that the parent Cut-off Creek received a 
small tributary from the northeast in the vicinity of the present site of 
Phillips School. The territory of this stream was invaded by the over- 
widened valley of Salt Creek. The sags, one near the center of seetion 35 
and one in the N. W. quarter section 35, are indications that the upper 
portions of two small tributaries of Cut-off Creek became engulfed in the 
widened valley of Salt Creek. In the case, however, of the tributary 
which came in near the present site of Phillips School, the whole of the 
area of the tributary became a part of Salt Creek valley. When the great 
‘curve had advanced far enough to come into the valley of Cut-off Creek or 
approach it through the valley of the tributary, piracy of the upper part 
of the parent Cut-off was effected. It is believed that the piracy was 
effected during the Pleistocene period. 
Statice Rejuvenation of Upper Cut-Off Creek Basin—The virtual division 
of the parent Cut-off Creek into Upper and Lower Cut-off creeks allowed 
the drainage waters from about 260 acres to enter Salt Creek directly, in- 
stead of having to flow some two miles farther before entering Salt Creek 
valley. Upper Cut-off Creek at the time of its diversion must have been 
perched 90 to 95 feet above Salt Creek valley. This is specifically indi- 
cated by the elevation of the old abandoned portion of the parent stream 
valley which is now the divide between Upper and Lower Cut-off creeks. 
(Figure 3.) The valley of Salt Creek at the place of the entrance of 
Upper Cut-offCreek upon it is 515 feet above sea level. The abandoned 
