12 Rhodora [JANUARY 
two or three miles below Madison. Some of the sources are at least 
3500 feet above the sea. At its mouth it is only 190 feet above sea- 
level. 
I have never visited the Sandy River Ponds, but I have explored 
several of the mountain brooks which are near the beginnings of the 
river. These are mostly noisy torrents and trout-brooks, full of huge 
rounded boulders and gravel, with only occasional specimens of 
Conioselinum chinense, Sium cicutaefolium and clumps of sedge (Carex 
torta and C. lenticularis), to differentiate their flora from that of the 
surrounding woods. 
From Phillips to New Sharon, some thirty miles, the river is a 
graded stream, with numerous meanders, broad intervales, ox-bow 
cut-offs and splendid terraces. These terraces are of sand and gravel 
above Farmington, with more clay below. Farmington village lies 
in part on the remnant of an old sand-plain, formed as a delta at the 
head of a marine estuary in the Champlain epoch, although its altitude 
is now 440 feet.! Nearly half of this sand-plain has been carried away 
by the river. Most of this work was probably done by the swollen 
stream which flowed from under the retreating glacier in the last days 
of the glacial period, when the ice was fast disappearing from the 
valley. Erosion has undoubtedly quickened greatly during the last 
125 years, since the intervales were cleared of the forest. Terraces of 
equal height are visible on both sides of the valley in many places, 
showing the original height of the glacial and post-glacial deposits. 
Their material is closely stratified. 
In summer the river is low and has little erosive power. Its gravelly 
beaches are covered in many places by Apocynum cannabinum and 
Prunus pumila, the two most common species. Salix cordata and S. 
lucida form immense clumps on this gravel, their height from a few 
inches to several feet. In sandy places there are tufts of Panicum 
tennesseense. Where the sediment is clayey it is easy to find Ranun- 
culus Flammula, var. reptans, Juncus nodosus and J. filiformis. 
Clumps of Carex torta are occasional. 
Perhaps the most characteristic habitat of this part of the valley 
is the alluvial thicket, which lines the shore in many places. The 
American elms are everywhere here, usually scattered, but very 
numerous. 'They are also the handsomest trees of the intervales, 
1 George H. Stone, The Glacial Gravels of Maine and their Associated Deposits, 
Monographs U. S. G. S. XXXIV, Plate II, page 484, etc. 1899. 
