RECENT DISCOVERIES IX THE ST. JOHN GROUP. 39 



narrow strips or wedge-shaped belts of small extent, which it will be 

 seen, are always closely connected with the older rocks. 



Lastly, the Lower Carboniferous rocks form basins of sediments, 

 filling in the hollows of the Cambrian and the older rocks and spread- 

 ing in the valleys. They are the youngest rocks visible in this area, 

 except the loose aggregations of Post-pleiocene gravel, sand and clay 

 which are not represented in this map. The Lower Carboniferous 

 shows two principal divisions — one reddish and of marine origin, the 

 other of grey color and containing scanty remains of land plants rare 

 in this part of the valley, but more abundant farther eastward. The 

 relative antiquity of these two parts of the formation has not been 

 determined. The grey beds are seen at Hasting's Cove, on the south 

 side of Kennejpecasis valley, and in Milkish passage on the north side. 



A great accumulation of boulder beds in the red division of this 

 system is well exposed on Long Island, where it comes out on the river 

 at the " Minister's " Face, a bold bluff extending from the outcrop of 

 Cambrian rocks half-way to the eastern end of the island. 



The Cambrian Rocks of the Kennebecasis Valley. — It will be 

 remembered that in the annual report of the Society for 1897 allusion 

 was made to work carried on on the Cambrian rocks of the Kennebe- 

 casis valley. We are now able to present some of the results of this 

 work. 



Sedimentation. — The sedimentation of the Cambrian in this valley 

 was found to show important differences from that of the valleys to the 

 north and south. 



All through the Etcheminian period, which preceded the true 

 Cambrian, this valley, with the surrounding territory north, south and 

 west, was elevated above the sea, and was apparently an island having 

 recently ejected volcanic rocks to the north-west and south-east of the 

 present Cambrian valleys. This island and the volcanic ridges 

 furnished sediment to the Etcheminian sea. 



When the Cambrian time arrived changes of level in the land took 

 place, so that while the Kennebecasis valley sank beneath the sea, 

 the ridges on either side of it, consisting, on one side of volcanic rocks, 

 and on the other of old Laurentian sedimentaries, remained aboA*e the 

 sea. Thus was the Cambrian sea in this district divided into three 

 areas of deposition, which to some extent were independent of each 

 other, but not so far as to make any very material difference in th e 

 faunas. 



