JV. IT. Darton — Magothy Formation of Maryland. 413 



ing two local eminences known as Maulden Mountain and Bull 

 Mountain. The western sides of these so-called mountains 

 are cut by the bay giving rise to very prominent bare bluffs 

 120 to 130 feet in height, in which the Potomac and Magothy 

 formations are well exposed. The Potomac beds in this region 

 are the typical variegated clays in which pink and buff colors 

 predominate but some reds and purples also occur. In the 

 upper part of the Potomac here there is a local bed of white 

 sand with more or less pink clay admixture which extends 

 for some distance along the bluff. The Magothy beds lie on 

 the usual erosion plane and are distinct from the Potomac 

 sands and clays below. They consist mainly of coarse, loose, 

 pure sands, regularly bedded except at a few points where 

 cross-bedding was observed. Several thin, local streaks of 

 clay are included and many large masses of brown sandstone. 

 Loose masses of this sandstone, in part pebbly, are prominent 

 in sandy areas between the higher portions of the ridge. The 

 Severn outliers are of weathered beds, consisting of dark gray, 

 fine, argillaceous sands below and more arenaceous, gray buff 

 members above, attaining in all a thickness of about forty feet. 

 Their entire separateness from the Magothy beds is exhibited 

 in several exposures. The higher summits about Maulden 

 Mountain are from 150 to 180 feet above tide level, and are 

 capped by outliers of Columbia of the high level series. 



The high bluffs along the south shore of the Sassafras River 

 near its mouth, expose the Severn beds in great force. Ap- 

 proaching Howell's Point the gentle southeast dip brings up 

 the Magothy beds which soon displace the Severn formation, 

 and extend westward nearly to the Point. They are the usual 

 moderately coarse sands but vary in color from pink to flesh col- 

 ored in greater part, with light brown streakings locally. Their 

 thickness is about twenty-five feet. They are loosely bedded, 

 with some cross-bedding. The underlying Potomac beds come 

 up in turn about 600 yards west of the first appearance of the 

 Magothy beds and the two formations continue to the end of 

 the bluffs, a short distance westward. The Potomac beds are 

 typical variegated clays comprising white, buff, pink, red, and 

 dark lead colors. Their surface is quite uneven and the clays 

 are separated from the Magothy sands by a thin, interrupted, 

 layer of impure limonite and coarse sand with a few scattered 

 quartz pebbles. The bluff is capped with Columbia members 

 which constitute about two-thirds of its height. 



Howell's Point is a tide marsh area, but a short distance 

 south the bluffs again extend to the bay ' shore and thence 

 continue to Still Pond. The Columbia formation extends 

 down to tide level for considerable distances in these bluffs but 

 the upper part of the Magothy beds is well exposed in the 



