28 



feet, and contains partly rounded pebbles of felsite in a felsitic paste. 

 It is followed by dark gray feldspathic amydgaloid and dark gray 

 porphyritic greenstone. 



About half a mile north-east of Dugald brook a traverse was made 

 across the Cambrian plateau. Except some purplish-gray sandstones 

 at the foot of the syenite hill, there are no exposures for 925 feet. 

 There is then a rising slope of 150 feet showing some exposures of the 

 Upper Etcheminian shales. Then ninety feet to a ridge of felsitc- 

 breccia with seams of gray shale ; this seems to be the equivalent of the 

 basal conglomerate of the St. John terrane seen in the gorge at Dugald 

 brook. Following this, in a space of seventy-five feet, there is a ridge 

 of dark gray ash-grit with a paste of a partly gray to dark gray felsitic 

 sand, partly a conglomerate with felsite pebbles, one inch across. The 

 dip here is S. 20 E. mag, < 70. This also is a part of the St. John 

 terrane. 



In this section the Coldbrook and Etcheminian terranes occupy a 

 a quarter more space than they do at Dugald brook, where, however, 

 they are vertical. 



Section on The small brook at the boundary of the Indian reservation of 



Boundary . . 



brook. -bscasonie on its eastern side, affords a somewhat interrupted section 



that throws additional light on the relation of the Etcheminian to the 

 St. John terrane. As at the former brook, the base of the Cambrian 

 rests against pre-Cambrian schists and intrusive rocks. The lowest 

 bed noticed was a reddish quartzite, not measured, but having a 

 thickness of about thirty feet. 



30 feet reddish-gray quartzites. 



Assise a . 



30 ' soft red sandstone, full of quartz veins and frag- 

 ments of feldspar. 



Assise b 35 " dark purplish-gray felsite-conglomerate. It forms, 

 a ridge broken through by the brook 



Assise c 25 " lower part, purplish-gray felsite shale. Ostra- 

 cods and small Brachiopods occur, but they 

 are rare. 



, f 20 " purplish-gray sandy shale. Fossils abundant. 

 Assise d { 



I 25 ' dark gray shale, Lingulepis Gregiva common. 



Assise e 25 " no exposures to the bridge at the road. 

 190 Division 1 of the Etcheminian. 



