214 Wisconsin Academy of Sciences^ Arts, and Letters. 



morainic accumulations of the " Coteac de Prairie,"^ and the 

 " Cobble Knolls " and " Antelope Hills. " 



These observations do not indicate a continuous, well defined 

 range, but seem rather to point to a half-buried moraine, that 

 only here and there, along its course, protrudes conspicuously, and 

 this is the impression gained from an inspection of the formation. 

 It is to be noted, as supporting this view, that, at least so far as' 

 the eastern side is concerned, this supposed moraine is flanked on 

 the exterior bv level plains, of smooth surface, often underlaid bj 

 sand and gravel, that seemingly owe their origin to broad rivers 

 or lakes that fringed the border of the glacier, in its advanced 

 state, when it probably discharged its waters over the moraine at 

 numerous points, rather than at one, or a few, selected points, as 

 would more likely be the case during its retreat, when accumula- 

 tions of water could gather along its foot, within the moraine, and 

 large areas be discharged at some single favorable point. But 

 on the inner side of the moraine, the surface, although nearly 

 level, in its general aspect, undulates in minor swells and sags, and 

 the drainage is imperfect. The substratum, instead of being gravel, 

 sand, or laminated clay, is generally a pebble or boulder clay. 

 Outside of the moraine, the existing surface contour was formed in 

 the presence, and, to some extent, under the modifying influence, 

 of a fairly established drainage system. But on the interior, the 

 drainage system has not, even yet, become fully established, much 

 less impressed itself upon the surface configuration, except in the 

 vicinity of the main rivers. 



The terrace-like ridge mentioned by Dr. White, and some of 

 the lines of hills described by Prof. Winchell in Minnesota, as 

 running in a similar direction, may be perhaps regarded as minor 

 morainic lines, stretching across the glacial pathway and marking 

 oscillations in its retreat, analogous to some quite clearly made 

 out in Wisconsin.^ 



This southern morainic loop is, of course, presumed to be older 

 than the Kettle range, and is here discussed because of the inter- 



1 See note of Prof. Mather, Nat. Hist. Sur. 1st Dist. N. T., p. 193. See also 2d Annnal Ee- 

 port Geol. and Nat. Bis. Sur. Siinnesota, by N. H. Winchell, pp. 193 to 195; also loc cit, ante. 

 a Geol. of Wis., Vol. II, 1876, p. 215 et seq. 



