220 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jail. 4, 



tinues very plentiful, with beds of gneiss interposed. It disappears 

 westwards at Wapescartoo River. The Falls of the Chaudiere River, 

 close to Hale Bay, pass over gneiss striking E.N.E., and vertical ; but 

 a white porphyritic granite is frequently seen close at hand. 



Oh the west side of Hale Bay I had an opportunity of taking strikes 

 and dips carefully in six places. They were always E.N.E., and in 

 one place indicated a small anticlinal (see Map, PI. X.). Since this 

 paper was written I have been pleased to find my notes confirmed by 

 the observations of Dr. Norwood, both in this locality*, and in the 

 neighbouring fin^ body of water. Lake Namaycan. 



This granite is remarkably porphyritic one mile west of Perch River, 

 the felspar-crystals varying from 1 to 10 inches in length, the 

 amorphous quartz-masses from 1 to 24 inches in diameter, and the 

 hexagonal crystals of yellowish silvery mica 1 or 2 inches broad. In 

 some places hereabouts the granite is of the kind called " graphic," 

 — as was remarked by Dr. Norwood of the granite not far from the 

 Chaudiere Falls at the S.E. corner of the lake. As might have been 

 expected from its strike, we find the mica-slate of Stokes Bay, re- 

 appearing at Perch Bay, with an interval of six miles of lake ; but 

 it is here coarser, more quartzose, often ferruginous, and in this 

 vicinity it distinctly runs into true gneiss. The nakedness of this 

 part of the coast permits a freer examination of its rocks than 

 elsewhere. 



From Wapescartoo River, through the Grand Detroit to Maypole 

 Island (sixteen miles), the only rock visible among the low woods is 

 exactly the same gneiss as that of Point Franklin on the opposite shore. 



This is particularly true at Point Observe, and on the east side of 

 Black Bay. For many square miles about Wapescartoo Bay it is 

 traversed everywhere by string-like headings and larger masses of 

 transparent amber-coloured quartz in long interrupted lines, with here 

 and there wandering veins of granite. 



The gneiss and mica-slate are conformable with each other and 

 with the slates of Seine Baj^ &c. Out of thirty-eight I'ecorded ob- 

 servations in this fifth division, twenty -four are to the E.N.E., eleven 

 E. by N., two nearly N.E., and one E.S.E. Of the twenty-eight 

 dips, fifteen are northwards, ten vertical, and three southwards ; the 

 last being near each other ; and two of them, although taken three 

 miles apart, evidently occur in continuations of the same strata. They 

 indicate small anticlinals. 



Sixth Division. — The sixth division occupies rather more than one- 

 third (the western) of the south shore of this lake, from ]Maypole 

 Island to Rainy River. 



For nearly eleven miles west of Maypole Island, to Point Logan, 

 chlorite-slatef and greenstone-slate predominate, and in precisely the 

 same relations to each other as in Indian Bay, &c., on the opposite 

 coasts. 



* Dr. Norwood found tourmaline, actinolite, and garuet here. 



t Dr. Norwood (Owen's Report, p. 310) informs us that there is much taleose 

 slate hereabouts. It may be so, but I saw none, although I cai'efully went over 

 this coast three times. I suppose him to mean fine soft chlorite-slatc. 



