210 
BULLETIN OF THE NATURAL HISTORY SOCIETY. 
were gradually cut out by backwardly extending branches from 
the lower Nerepisian, which thus very early captured the lower 
Rusagonian, and soon after the lower Keswian (whence the lower 
courses of these rivers have had time to be much altered by minor 
later changes), while a branch of the lower Rusagonian early 
extended back and captured the Keswian, forming the present St. 
John from the foot of Long Island to Jemseg. It was no 
doubt a similar erosion which formed the great Hammond River- 
Loch Lomond-Little River valley, and another of analogous 
character which formed the northeasterly part of the Nerepis 
River. 
In the meantime, also, a branch parallel with the Oromocto 
was eroded back from the Keswian near the mouth of the present 
Keswick, to capture the Rusagonian at Kelly’s Creek.* It is 
true this part of the river does not now run in the softer Carboni- 
ferous rocks, but remnants of those rocks exist, showing that it 
formerly did so. The erosion of this band did not stop here, 
however, but extended along upper Gardens Creek. It was very 
probably a similar erosion starting in bands of soft rocks now 
removed which formed the northeast branch of Nacawic and the 
St. John thence to Pokiok, thus capturing upper Nerepisian 
waters. Something of the same kind would explain the north- 
east and southwest parts of Eel River (and even the course of the 
main iMatawamkeg beyond). During this time also the great 
branches of the Keswian were eroding eastward, originating the 
Washademoak, Grand Lake, Little River and the Nashwaak, a 
regular radiating series, capturing in early times for the great 
Keswian the old Nashwian, if that really existed. We can trace 
also similar effects on the other rivers. Thus it was probably a 
similar erosion which formed the Magaguadavic northeast of 
Trout Brook, turning one branch of this valley into another. 
Such an erosion northeast from the Chepednian valley also pro- 
bably formed the St. Croix from iMud Lake to Scott’s Brook (and 
Trout Brook beyond), thus early capturing the upper Passama- 
*Professor Bailey gives evidence to show that this part of the river occupies a channel 
dating back to pre-Carboniferous times, which makes its explanation all the simpler. (On 
the Physical and Geological History of the St. John River, New Brunswick. Trans. Royal 
Soc. Canada, I, 1883, iv, 283). 
