LAKE KANKAKEE. 329 



written, as well as by Prof. A. H. Purdue and the writer. The limits have 

 been determined with considerable accuracy, and the general features of 

 the area have also been studied. The phenomena, as will be seen, are of a 

 peculiarly puzzling nature, and as yet a fully satisfactory interpretation of 

 them has not been reached. 



EXTENT OF THE SAND. 



Beginning at the northeast and passing southward, the sand is found to 

 have its eastern limit at the border of the Maxinkuckee moraine of the 

 Saginaw ice lobe in western Marshall County, Indiana (see PI. VI). A few 

 dunes occur on the moraine, but the continuous sand follows approximately 

 the west border. Farther north, in St. Joseph County, a gravel plain occu- 

 pies the outer or west border of the Maxinkuckee moraine. The moraine 

 swings eastward along the north side of Tippecanoe River in northern 

 Fulton County, and a narrow sand}' belt extends up the Tippecanoe 

 Valley along the outer border of this moraine as far as Rochester, but the 

 east border of the main sand area continues southward through western 

 Fulton County and northwestern Cass County to the vicinity of Lake 

 Cicott. Purdue reports that for about 9 miles north of Lake Cicott a well- 

 defined sand ridge forms the east border of the till plain that descends 

 westward to the Tippecanoe River. This ridge turns abruptly westward 

 near Lake Cicott and is nearly continuous to the Tippecanoe Valley at 

 Monticello. For a part of this course the ridge lies along the north slope of 

 a moraine of the Erie lobe. After crossing Tippecanoe River at Monticello 

 the moraine turns south, while the ridge continues in a course slightly 

 south of west about to the line of White and Benton counties. From this 

 point a narrow sand ridge has been traced by Purdue in a course north of 

 west nearly to Kentland, Indiana. There is, however, very little sand on 

 the surface for several miles north from this ridge, and he did not succeed 

 in tracing the ridge farther west. 



Purdue reports that there is a somewhat broken east-to-west sand ridge 

 north of Indian Creek in southeastern Pulaski County, which passes through 

 the village of Rosedale (Oak post-office), where it presents large dunes, and 

 thence turning northeastward, terminates at a gravelly knoll in the north- 

 east comer of T. 29, R. 1 W. The area from this ridge north to and beyond 

 the middle of Tippecanoe Township is an extensive sandy plain, with the 



