GREAT    NORTHERN    INTERIOR   OF   CANADA.  535 
schist,  porphyry,  granulite,  red  jasper,  chloritic  schists,  etc.  The 
majority  of  the  lithological  specimens  correspond  with  the  rocks  of 
the  Huronian  series;  Laurentian  types  are  absent,  and  the  probabili- 
ties are  that  Huronian  rocks  prevail  all  along  the  northwest  coast 
of  Hudson  Bay,  from  Eskimo  Point  to  Chesterfield  Inlet,  and  again 
at  Repulse  Bay.  The  widely  extended  areas  of  massive  granitoid 
character  about  Hudson  Bay  are  regarded  as  Primitive  gneiss,  and 
are,  therve  is  little  doubt,  more  ancient  than  the  regularly  stratified 
gneisses  which  prevail  in  the  Ottawa  Valley.  The  Huronian  rocks 
of  the  region  are  unlike  those  on  the  north  shore  of  Lake  Huron, 
consisting  of  massive  diorites,  argillaceous  and  dioritic  slate  con- 
glomerates, granite  syenites,  schistose  and  jaspery  iron  ores,  lime- 
stones, dolomites,  and  imperfect  gneisses,  with  a  great  variety  of 
schists.  The  Manitounuk  series  is  largely  made  up  of  rocks  of  vol- 
canic origin. 
Bell,43  in  1887,  reports  on  explorations  of  portions  of  Attawapis- 
kat  and  Albany  rivers.  Various  granites,  gneisses,  and  schists 
are  found  at  Pelican  Lake,  Lake  St.  Joseph,  the  upper  sections  of 
Albany  and  Boulder  rivers,  and  Lake  Lansdowne.  At  Lake  St. 
Joseph  a  conglomerate  is  found.  The  granites  and  gneisses  are  placed 
with  the  Laurentian  and  the  schists  and  conglomerates  with  the 
Huronian. 
Dawson,44  in  1887,  as  a  result  of  an  exhaustive  review  of  the  litera- 
ture of  northern  Canada,  states  that  Archean  or  Eozoic  rocks  are 
dominant  in  the  northern  part  of  the  continent.  They  also  form  the 
greater  part  of  Greenland,  and  doubtless  underlie  at  no  great  depth 
the  entire  Arctic  archipelago.  While  the  information  available  is 
sufficient  to  indicate  the  existence  of  the  different  subdivisions  of  the 
Archean  which  are  met  with  in  the  southern  portion  of  Canada,  in- 
cluding the  lowest  Laurentian  or  granitoid  gneiss  series,  the  Middle 
Laurentian,  possibly  the  peculiar  rocks  classed  as  the  "  Upper  Lauren- 
tian," and  certain  of  the  more  schistose  and  generally  darker  colored 
and  more  basic  rocks  classed  as  Huronian,  it  is  far  too  imperfect  to 
admit  of  the  separation  of  these  subdivisions  on  the  map.  It  is  evi- 
dent that  the  Huronian  is  represented  in  parts  of  the  west  coast  of 
Greenland,  and  it  is  probably  also  recognizable  on  the  Labrador 
coast  and  on  the  west  coast  of  Hudson  Bay.  The  occurrence  of  well- 
stratified  gneisses  with  mica  schists  and  crystalline  limestones,  with 
associated  graphite  and  magnetite,  appears  to  indicate  the  presence 
of  Middle  Laurentian.  These  rocks  occur  on  the  southern  pari  of 
Baffin  Land,  Frobisher  Bay,  Cumberland  Sound,  and  Melville  Penin- 
sula. The  term  Cambrian  is  made  to  include  all  rocks  above  the 
Huronian  to  the  base  of  the  Cambro-Silnrian.  Extensive  areas 
placed  in  the  Cambrian  on  the  Arctic  coast  and  in  the  vicinity  of 
Coppermine  River  are  analogous  in  character  to   those  of  the    Ke 
