56 BIG SPRING PRAIRIE. 
In the vicinity of new road No. 1, ditches were dug 
years ago along the eastern and western margins. As 
a result of this, the level of the soil along the margins 
was lowered, while accumulation still continued in the 
middle; accordingly at the time of the digging of the 
ditches along the middle of prairie, this portion was 
higher than that along the edges, presenting the phe- 
nomena frequently observed in undrained Sphagnum 
swamps. At present, there are two higher portions be- 
tween the middle ditch and either margin of prairie. 
Although this portion was the highest part of this sec- 
tion, it possessed distinct and characteristic bog feat- 
ures. A short distance south of the divide there were 
two springs, and north of it three or more springs, of 
which Ox Spring was the most important. Some of 
these prairie springs are at present simply large 
depressions, filled with water during wet seasons, and 
in dry seasons, barely moist. The abundance of 
springs in this locality and their former importance, 
in connection with its position between the two ridges, 
accounts fully for its being the most elevated portion 
of prairie. The abundance of water, discharged by 
these springs, before the ridges were so extensively de- 
forested, was especially conducive to the rapid accumu- 
lation of plant remains, as it prevented much loss from 
oxidation. ‘This area seems to have possessed the ne- 
cessary conditions for a Sphagnum swamp, but careful 
microscopic examination of the soil from this vicinity 
failed to reveal any traces of Sphagnum. Other mosses 
chiefly Hypnum species are quite abundant in the 
spring of the year. Since beginning the study of this 
section, this portion in immediate vicinity of Ox Spring 
has been brought under cultivation, and displayed a 
divergence from the general character of the surface 
soil of the prairie. Irregular patches and streaks of 
marly deposits occurred here and there. The origin of 
these deposits is due in great part to the lime deposited 
