GLACIAL GRAVELS OF COASTAL EEGION. 379 



described near Freeport (pp. 369-370). It will be convenient to refer to 

 them as gravel massives. They are not so common a feature of the discon- 

 tinuous osars as of the long osar and broad osar systems. 



3. Reticulated eskers consisting of two or more reticulated ridges 

 '.nclosing kettleholes, but not ending in delta-plains, such as the gravels 

 near East Monmouth. These are a not uncommon form of the gravels. 

 The material is nowhere very fine, showing that the waters were not much 

 checked. The problem of the reticulations will be refei-red to hereafter. 



4 Cones, domes, and lenticular short ridges, all with broadly arched 

 cross section. As a class these deposits have rather gentle lateral slopes 

 and their shapes resemble the drumlins or lenticular hills of till. The 

 variety of individual forms is very great. All gradations can be found 

 between domes and lenticular mounds on the one extreme and long ridges 

 on the other. While they vary in size, height, and slope, yet the prevail- 

 ing lateral slopes of the gravels that were below the sea are more gentle 

 than those above that level. 



GLACIAL GRAVELS OF THE COASTAL REGION. 

 RELATIONS OP GLACIAL GRAVELS TO THE POSSILIFEROUS MARINE BEDS. 



The glacial gravels are found in three relations to the marine clays. 

 First. The gravels have the same level as the clays and pass by degrees 

 directly into them. This is the characteristic relation of the glacial deltas 

 and marks the coarser glacial sediments as being laid down simultaneously 

 with the clays. Second. The clays overlie the glacial gravels, either wholly 

 covering them or covering' their base. The 

 gravels were first deposited within ice walls, 

 and subsequently, after the ice had melted, 

 the clays were deposited. This arrange- 

 ment is so common that for a long time 1 

 supposed it and the third named to be the 



1^-1, -I ^ ^^'^' 27- — Sheet of marine clay overlying 



only ones, the first being accounted lor as 

 due, not to original deposition, but to the subsequent action of the sea 

 in remodeling the sediments. This was based on an exaggerated idea of 

 the power of the sea to erode and transport. Third. The sand and gravel 

 of the upper parts of the osar gravels overlie the fossiliferous clays which 

 cover the bases of the same kames or osars. This happens in many cases, 



