CRYSTALLINE SCHISTS NORTH OF LAKE SUPERIOR. 397 
are to be taken as representing the nature of the rocks only in the most 
general way. Bell describes these schists as always standing at a high 
angle, with a strike varying between N. 25° E. and N. 80° W. The 
quartzite, chert, ribboned jasper and iron ore of these rocks certainly have 
much the look of the recognized Huronian. With regard to the other 
rocks it is impossible to draw any conclusions from the very general de- 
scriptions given; while there is no evidence presented showing that part of 
the so-called Huronian rocks might not really belong with the gneiss, 
which in some places seems to grade into mica-schist. 
From the statements of Bell, N. H. Winchell, and Chester, it is plain - 
that the schistose belts (or belt) of the Thunder Bay region continue for 
over two hundred miles to the southwestward, at a similarly short distance 
north of the northern boundary of the Animikie rocks, and similarly in- 
volved with gneiss and granite. Still farther north, in the vicinity of Rainy 
Lake, other like schistose bands occur, as shown by. Bigsby, Bell, and 
other geologists. 
The band of schists running west and south from the northern part of 
Saganaga Lake, on the national boundary, for instance, is described by 
Bell’ as consisting of “rusty, brown, altered sandstone containing small 
white quartz pebbles;” “soft green argillite;” ‘“dioritic schist;” “cherty 
felsitic slate;” ‘‘siliceous schist;” ‘“chert-rock,” which “resembles the chert 
near the base of the Upper Copper-bearing Series,” 7. e., the Animikie 
Group; “gray granular quartzite;” and ‘fine-grained glossy clay-slate.” 
All of these rocks are said to stand nearly vertically, inclining slightly on 
one side or the other, and to strike from 15° to 80° west of south. 
A different belt of schistose rocks was crossed farther west by N. H. 
Winchell in making a canoe trip from Bois Blane Lake, on the national 
boundary, to Vermillion Lake, in 1879. He speaks of these schists as soft 
greenish slates, siliceous slates, and hornblende rocks and schists of several 
kinds,” trending in a general southwesterly direction, and standing always at 
a very high angle, and apparently conformable with the associated gneiss. 
From the descriptions given by Winchell, and from specimens sent me by 
? 
1 Report of Progress of the Geological Survey of Canada, for 1872~73, p. 93. 
8Ninth Annual Report of the Geological and Natural History Survey of Minnesota, p. 91, et seq. 
