G. II. Stone — Glacial Sediments of Maine. 137 



spaces several or many miles in diameter. Thus in that part of 

 Maine west of Sebago Lake and south of the Androscoggin 

 River, all the larger gravel systems are connected with each 

 other, not only at the great marine deltas (the deltas of the 

 glacial rivers are here so large that those of adjacent rivers 

 coalesced) but above the contour of 230 feet we find each 

 gravel series connected with the rest by lateral series. The 

 most remarkable of these reticulations of the plains themselves 

 are found in the towns of Fryeburg, Brownfield, Porter, Hi- 

 ram, Cornish, Parsonsfield and Newfield. The country is very 

 hilly. The principal streams of the region, the Great and 

 Little Ossipee Rivers, flow in east and west valleys, while their 

 lateral tributaries occupy a series of north and south valleys. 

 Four series of gravel plains, each from one-sixteenth to three- 

 fourths of a mile wide, traverse this region along the north 

 and south valleys, thereby crossing all the east and west valleys. 

 This course leads them in several places up and over hills more 

 than 200 feet high, measured on their northern sides, and in 

 one case over a hill about 400 feet high. Every few miles the 

 north and south series are connected by transverse gravel plains 

 of similar character. Most of these lie in the east and west 

 valleys, but part of them go over hills. The complexity of the 

 long reticulations can only be appreciated by inspection of the 

 map. The gravel plains in question take the form of osar 

 plains alternating with reaches of plains composed of reticu- 

 lated kames. In three places they are connected with the 

 great kame-plains mapped by Mr. Warren Upham as extend- 

 ing in New Hampshire from Conway southward. 



My paper on the kames of Maine read before the Boston 

 Society of Natural History in 1880 made it certain that the 

 longer gravel systems of Maine often have branches converg- 

 ing toward the south like tributaries of the ordinary rivers that 

 flow southward. It is now certain that many osars and osar- 

 plains divide into branches which diverge toward the south, 

 like the delta branches of rivers. This does not refer to 

 branches which presently came together again (the phenom- 

 enon of the reticulated kames) but to branches that diverge for 

 long distances and some of them end in marine deltas ten or 

 more miles apart. In these cases the branches do not come to- 

 gether at any place after divergence. This can be accounted 

 for in different ways. 



1. It is probable that in case of some of the diverging or 

 delta branches, the rivers which deposited the diverging lines 

 of gravels flowed simultaneously in both the channels like the 

 delta branches of the Mississippi. 



2. In some places one of the lines of diverging gravels is 

 found following a slope of natural drainage, while the other 

 goes over hills at a higher level. Such for instance are the 



