SOME GLACIAL WASH-PLAINS. 95 



The Elizabeth Island moraine presents no outwash 

 plains above the sea-level. The moraine itself, according 

 to investigations carried on bv C. W. Coman under 

 Professor Shaler, overlies stratified drift, which appears to 

 be of an earlier date than the halt of the ice-sheet at this 

 line. Neither is a sand-plain developed above sea-level 

 in front of the Charlestown moraine. From analogy of 

 this line of moraine with the similar deposits on Nantucket, 

 we should expect to find the sand-plains of that stage from 

 half a mile to a mile south of the moraine and l)eneatli 

 the present sea-level in these areas, the moraine itself 

 being a submarginal deposit. 



Plains of the Narragansett Bay region. — The principal 

 features of the numerous plains in the Narragansett Bay 

 area have been described in my paper of 1890. They 

 need be referred to here only in connection with the lines 

 of retreat which they mark. 



The Middlehoro moraine. — The southeastern border of 

 the Carboniferous area from Fall River eastward is more 

 or less topographically shown by a low elevation of gra- 

 nitic hills. Closely following this line and in the sedi- 

 mentary, lower area is a recognizable line of glacial, 

 frontal accumulations, perhaps best shown at Middleboro 

 (30), where, east of the town, morainal hills, with crum- 

 pled gravels, lie on the northwest border of stretches of 

 sand-plain extending southeastward. This tj'pe of topog- 

 raphy extends northeastward to Kingston, beyond which 

 it merges into the complex morainal and fan- cone topog- 

 raphy of the Plymouth interlobate moraine (32). Nu 

 merous streams head in the belt, flowing to the southeast 

 or northwest, and showing manifest derangement by the 

 distribution of the deposits. The Lakeville lakes (28) 

 lie on the outer margin partly enclosed by earlier drift. 

 Great Cedar Swamp lies in the unfilled area back of the 

 morainal line. 



