THE BLOOMINGTON MORAHSTIC SYSTEM. 259 



more gradual descent to a plain which continues descending- to the Vermilion 

 River. This eastern portion of the ridge has numerous small knolls 10 to 

 20 feet in height and occasional shallow basins. From Cropsey westward 

 the expression is somewhat weaker, though a relief of fully 30 feet is main- 

 tained as far west as the Chicago and Alton Railroad north of Lexington. 

 There is also sufficient undulation of the' surface to give this belt decided 

 contrast to the plains on its border, swells 10 to 20 feet in height being quite 

 common. West from the railroad the belt is definitely ridged for a few miles, 

 but near Elpaso it becomes so obscure that further tracing and correlation 

 has not been attempted. There are many places toward the north and west, 

 in northeastern Woodford, eastern Marshall, southwestern Lasalle, and east- 

 ern Putnam counties, where, for a space of a square mile or more, the surface 

 is quite as undulatory as in this morainic belt. It is possible that more 

 detailed study will bring out a connection between these several undulatory 

 tracts by which they may be thrown into a single belt. Possibly the divide 

 between Vermilion River and tributaries of the Illinois flowing- directly 

 westward will prove to be the axis of such a belt. This divide, wherever 

 it has been crossed by the writer, presents a slightly undulatory surface. 

 The majority of the strongly undulatory belts, however, are found a short 

 distance west of this divide. The surface is generally more undulatory 

 west from the divide than east from it. 



chatsworth-cayuga Ridge. — From the reentrant angle at Chatsworth in south- 

 eastern Livingston County northwestward nearly to Forrest the inner of the 

 two weak members of this morainic system has sharp knolls inclosing basins, 

 but their height is less than in the reentrant angle, seldom exceeding 25 feet. 

 They occur on the slope as well as on the crest of the moraine. From the 

 vicinity of Forrest northwestward for a few miles the moraine has a well- 

 defined crest and is characterized by gentle swells 10 to 20 feet high. In 

 sec. 34, Pleasant Ridge Township (T. 27, R. 7 E.), the single crest gives 

 place to a double one, and two ridges are maintained from this point north- 

 westward to the north branch of the Illinois- Vermilion River, the outer ridge 

 coming to that river in sec. 14, T. 27, R. 6 E., while the inner comes to it in 

 sees. 7 and 8, T. 27, R 7 E. The outer ridge has a billowy crest,- consisting 

 of a series of slightly elliptical knolls, 25 to 40 feet high, 40 to 50 rods 

 long, and about one-half as wide. These constitute an almost complete 



