66 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 



