TEIBUTARIES OF LAKE ERIE. 213 



line of discharge for the preglacial Upper Allegheny.' The greater part 

 of the present basin of Cattaraugus Creek appears to have been tributary 

 to the old Upper Allegheny from the east and to have joined that valley 

 near the mouth of Clear Creek, opposite Versailles. The old basin of 

 Cattaraugus Creek included the headwater portions of Ischua Creek and 

 probably of Great Valley Creek, now tributary to the Allegheny. The old 

 divide on Ischua Creek appears to have been just south of the village of 

 Ischua, fully 15 miles from the present divide near Machias. The present 

 drainage departs considerably from the preglacial line near the junction of 

 the South Fork with the main stream. The South Fork appears to have 

 formerly taken a course east of north from the village of Cattaraugus, past 

 Waverly, to join the east or main fork about 5 miles above the present point 

 of junction. The united stream then took a northwestward course, passing 

 just south of Collins Center and Lawton to the lower course of Clear Creek. 

 Between the old junction and the present one Cattaraugus Creek is flowing- 

 through a rock gorge no wider in places than the bed of the stream. South 

 Fork also enters a similar gorge about 5 miles northwest of Cattaraugus, 

 which continues to the junction with the main creek. A short distance 

 below the present junction with the main creek the old valley of the Upper 

 Allegheny is entered. The present creek does not traverse the deepest 

 portion of that old valley, but follows its west bluff, and for a few miles in 

 the vicinity of Versailles it is cutting a rock gorge in the face of that bluff. 



The drainage basin of Cattaraugus Creek is limited on the north and 

 east by morainic belts. It is scarcely jarobable that these follow a preglacial 

 divide, though the position of the preglacial divide has not been fully deter- 

 mined. Possibly the headwater portion of Cattaraugus Creek discharged 

 north w;estward through valleys now tributary to Buffalo Creek. 



The old drainage basin of which Cattaraugus Creek formed a part is 

 discussed in connection with the Upper Allegheny River (pp. 129-132). 



SMALL TRIBUTARIES BETWEEN CATTARAUGUS AND CONNEAUT CREEKS. 



The tributaries of Lake Erie between Cattaraugus and Conneaut creeks 

 find their sources in the prominent escarpment whicli borders the lake in 

 southwestern New York and northwestern Pennsylvania. Their sources are 

 seldom more than 16 miles distant from the lake, and the longest streams are 



1 Am. Jour. Sci. , 3d series, Vol. XLVII, 1894. 



