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BULLETIN OF THE NATURAL HISTORY SOCIETY. 
a pre-Silurian sea ; and the present Nepisiguit above and below it 
were blanches entering it at different points. (See accompanying 
map). This, I believe, was the case. The source of the west branch 
of this river would probably have been near the present Silver Brook, 
perhaps that brook itself. A branch must have eroded its way north- 
ward deeply enough so that the choking of the Nepisiguit Lake- 
Nictor Valley with Glacial drift (or possibly some earlier cause) turned 
the Nepisiguit Lake waters from the Tobique into the Nepisiguit, 
thus explaining the curious southerly bend of the valley at this point. 
Possibly the Third Fork Brook is the continuation of this branch. 
The source of the eastern branch must have been somewhere to the 
eastward of Indian Falls. In fact the valley continues to narrow 
eastward until, just below the Forty-mile Brook, the river bed nearly 
fills it ; but probably the ancient source was not so far east. The 
geography of this upper part of the river appears to me not to have 
been altered materially by the Glacial period. The trains of boulders 
forming the occasional rips are no doubt remnants of old Glacial dams, 
the gravel of which is now distributed along the river bed. The great 
depth of this part of the valley has prevented the formation of Glacial 
falls.* 
At Indian Falls the river drops a few feet amongst huge boulders 
and over ledges evidently in a post-Glacial channel. I could not 
identify the pre-Glacial channel, but from the top of Mount Denys 
(Bald Mountain) one can see what appears to be an old channel 
marked by a heath on the north bank. 
Below Indian Falls the character of the river changes entirely. 
Its current is much swifter and more broken, both by huge boulders 
and by more frequent ledges. The country rapidly diminishes in 
elevation, soon becoming a great peneplain, into which the river has 
cut some 200 to 300 feet. The valley continues to narrow to some- 
what below Forty-mile Brook, where, as already stated, the river bed 
nearly fills it. Below this it broadens a little, at least in places, until 
Nine-mile Brook is reached. Along this part of the river are some 
fine lofty gravel terraces culminating in a particularly fine one, speci- 
ally mentioned by Mr. Chalmers, just below the mouth of that brook. 
Just below this terrace occur huge boulders in great number, forming 
• On the relationship of depth of valleys to absence of falls. See earlier note 8, 
(Bulletin xvi, 52). 
