256 INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



Divisions IV and V. — Red and green shales of Cape Gaspe; red and green slates and sandstones of Mount Wissick; 

 similar slates on Fish Eiver (Eagle Lake) and Aroostook River, Maine; red and green slates of Grand River and 

 Carleton County, New Brunswick; often iacluding argilkceous iron ores. (?)Felsites and associated trappean rocks 

 of Campbellton and Bay Chaleur, Moose Mountain, New Brunswick, Haystack and Spider Lake, Maine. 

 Division VI. — Gray, often nodular or columnar limestones, abounding in fossils. 



Upper limestones of Cape Gaspe; middle and upper rocks of Moimt Wissick, regarded as equivalents of the 

 lower portion of the Lower Helderberg. 



Fossiliferous limestones of Square Lake and Ashland, Me.; Lower Helderberg. 



Fossiliferous limestones of Carleton County, New Brunswick. 



Fossiliferous slates and sandstones of Metapedia River, Restigouche, Victoria, Madawaska and Carleton counties, 

 New Brunswick. Similar slates, etc., of Aroostook County, Me. Lower Helderberg (?). 



Silxirian strata of southern New Brunswick (Charlotte County) and adjacent 

 parts of Maine have in later years been found to be more extensive than had been 

 supposed, the Silurian age of certain metamorphic rocks and of slates previously 

 assigned to older horizons having been determined. '''' The geologic relations are simi- 

 lar to those about Penobscot Bay, Maine. (See L 19, pp. 134-135.) 



L-M 21. NEWFOUNDLAND. 



Under the heading "Upper Silurian series" Murray, in 1864, described con- 

 glomerates, slates, and mica schists, together with intrusives of granitoid character, 

 all of which are exposed in sections on Jackson's and Sop's arms of White Bay, 

 Newfoundland. Murray ®°* states : 



Jackson's Arm runs into the land nearly at right angles to the strike, and here these upper 

 rocks have a transverse breadth of about 2 miles. The following section of them, in ascendiag 

 order from the mica slates on which they are seen to rest, is taken from the north side of the arm, 

 on which the measures appear to be broken by three considerable faults, causing what are 

 supposed to be modified repetitions of some of the masses. 



Feet. 



1. Coarse conglomerates, with a light-gray arenaceo-micaceous slaty matrix which is slightly 



calcareous. The masses inclosed consist of pebbles and bowlders of gneiss, large rounded 

 fragments of whitish or light-gray mica slate, some of a darker-gray greenstone, reddish- 

 gray quartzites, and occasional smaller masses of limestone ; among these there is a good deal 

 of finer ma,terial of the same character, slightly calcareous, and mica schist runs in irregular 

 flakes and patches in the general direction of the stratification, but its cleavage often par- 

 tially conforms to the rounded surface of the bowlders and pebbles. The beds are very 

 massive, and they appear to be divided by gray micaceous schist 400 



2. Sea-green slates, occasionally interstratified with dark-gray or blackish fine silky-surfaced 



slates, some of which are harder than others 300 



3. Gray, coarse, rough arenaceo-micaceous scbist, frequently passing into a fine conglomerate, 



with pebbles similar in mineral character to those of the coarse conglomerates beneath, but 

 none of them exceediag the size of a hen's egg; the pebbles are sometimes arranged in regu- 

 lar layers, parallel to the stratification; bands of dark-gray clay slate are occasionally inter- 

 stratified in the mass 400 



4. Gray micaceous and arenaceous slates .■ 250 



5. Green and black slates at the base, succeeded by gray arenaceous slate, which is interstrat- 



ified with thin bands of sandstone ,. 650 



6. Green, bluish, and blackish sktes, interstratified -with gray flaggy sandstones; the slates 



inclose nodules of pinkish calc spar, and veins of the same cut the strata 250 



7. Grayish-blue limestone in a single bed 7 



8. Gray calcareo-arenaceous slates, interstratified with grayish sandstones, with a heavy mass 



of gray, white-weathering sandstone at the top 543 



2,800 



The above section can only be considered as giving an approximation to the truth. The 

 three faults which dislocate the rocks and are all considered to be upthrows on the east side 

 render it difficult to foUow the sequence with exactitude; and. some of the masses, which are 



