2 18 Wisconsin Academy of Sciences^ Avis, and Letters. 



ridge-like morainic accumulations, and their presence, in sharp 

 outline, is not to be expected. In the vicinity of Ligonier, in 

 Noble county, there is a feeble, but somewhat characteristic devel- 

 opment of some of the features of the formation. So also, in 

 the vicinity of Eome and La Grange to the northeast. Between 

 La Port and Otis there is a kindred, though somewhat peculiar 

 formation, but I am in doubt as to its true character. 



On entering Michigan, we find the formation more unequivo- 

 cally developed. Just north of Siurgis, which is near the south- 

 ern line of the state, the formation appears in marked develop- 

 ment. It does not attain a great altitude, but presents the 

 peculiar strongly undulating and hummocky contour, and the 

 coarse, mingled material, characteristic of the deposit. It may 

 be seen to advantage on the line of the Grand Eipids & Indiana 

 R. R To the northeast in the vicinity of Albion, it may be seen 

 from Spring-port on the north, to Condit on the south. It is here 

 broad and flat, and superficially composed of gravel, for the 

 greater part, but some of the deeper excavations reveal the char- 

 acteristic coarser material. On the Michigan Central R. R., the 

 formation may be observed between Jackson and Dexter, the 

 most prominent portion being between the stations Francisco and 

 Chelsea. It is not very prominent on the immediate line of the 

 road, which was doubtless selected to avoid it, but in the vicinity 

 it rises into prominent hills and ridges. Some of these, on the 

 north, are conspicuous objects at considerable distances. Still 

 farther to the northeast, my friend. Dr. D, F. Boughton, whose 

 identifications I have elsewhere verified, informs me that the 

 range is well developed in Oakland county, and is finely exhib- 

 ited near the line of the Flint & Pere Marquette R. R, between 

 Plymouth and Holly. Still farther to the northeast, it may be 

 seen at great convenience and advantage, along the Detroit & 

 Milwaukee R. R. from Birmingham, below Pontiac, to Holly. On 

 the flanks, its features are subdued, the hills and ridges being 

 rather low, with more or less level surface between them, and the 

 superficial sands and gravels are prevalent; but from Waterford 

 to beyond Clarkston, the range has a fine, though irregular devel- 

 opment. The hills rise with characteristic contours, to an esti- 



