KATAHDIN SYSTEM. 115 



lakes or in a plexus of sediment-clogged ice channels which were practicallv 

 equivalent. 



Length, about 126 miles. 



STACEYVILLE-MBDWAY BRANCH. 



A nearly continuous ridge beg'ins in the southern part of Staceyville 

 and traverses a very level region for about 15 miles, when it approaches 

 the Salmon Stream. Its course then lies along the west side of that stream 

 for several miles, and not far north of the Penobscot River it expands into 

 plains of sand and gravel, which are rather level on the top, so much so as 

 to make it probable that they are a delta deposit, either in a glacial lake 

 which then extended across the Penobscot Valley and for a short distance 

 up the valley of the Pattagumpus Stream, in an estuary, or in the sea. 

 The sea certainly extended for several miles up the Penobscot above Mat- 

 tawamkeag, but how far I am as yet unable to determine. 



Length, about 20 miles. Much information as to the region about 

 Medway has been received from Col. J. F. Twitchell. 



SALMON STREAM BRANCH. 



This has been traced northward along the valley of Salmon Stream to 

 Salmon Stream Lake. It joins the Staceyville branch about 2 miles north 

 of the Penobscot River. 



Leng'th, about 10 miles. 



SAM AYERS STREAM BRANCH. 



This osar is said to extend as a two-sided ridge 6 or more miles along 

 Sam Ayers Stream, above its junction with the Mattamiscoutis Stream. 

 The connections of this series are uncertain. The Champlain sea extended 

 up the valley of the Mattamiscoutis for several miles above South Lincoln, 

 and if this short glacial stream emptied into the sea at some place in that 

 valley, the series would end at that point in a marine delta. If so, this may 

 be an independent system. But I found several domes of glacial gravel in 

 that valley of the Mattamiscoutis nearly opposite South Lincoln. These 

 may be either an extension of the Sam Ayers Stream series or simply out- 

 lying ridges of the main Katahdin system, which lies less than a half mile 

 away across the Penobscot. My own exploration did not extend far up 



