vanhisb.i  EASTERN    CANADA    AND    NEWFOUNDLAND.  23 1 
county,  which  may  be  Cambrian.  Scattered  through  all  the  above  arc 
igneous  rocks  such  as  granite,  syenite,  porphyry  and  trap,  which  may 
occur  associated  with  rocks  of  any  age.  The  Portland  group  is  in  al- 
most entire  conformity  with  the  Coldbrook  group.  The  lithological  re- 
semblance of  the  Coldbrook  group  (7,000  feet  thick)  with  the  Huronian 
is  very  close.  The  presence  of  graphite  in  the  Portland  and  St.  John 
groups  is  regarded  as  evidence  of  life. 
The  extreme  metamorphism  of  the  Portland  group  is  evidence  of  its 
great  antiquity.  This  age  would  never  have  been  doubted  were  it  not 
for  the  intimate  association  and  conformability  with  the  beds  of  the 
overlying  groups,  which  are  unquestionably  Upper  Devonian,  and  the 
Portland  was  supposed  to  represent  either  a  portion  of  the  Lower  Devo- 
nian or  possibly  the  upper  part  of  the  Silurian.  During  the  deposition 
of  the  Azoic  and  Silurian  ages  a  long  period  of  repose  prevailed,  broken 
only  by  the  volcanic  activity  of  the  Coldbrook  group.  The  Bloomsbury 
rocks  associated  with  rocks  unquestionably  of  Upper  Devonian  age 
are  referred  to  the  same  horizon.  At  one  place  the  Coldbrook  group 
overlies  the  St.  John,  its  position  being  due  to  a  reverse  folding  caused 
by  a  ridge  of  eruptive  syenite.  The  Kingston  group  on  its  general 
lithological  character  and  stratigraphical  relations  is  provisionally  re- 
ferred to  the  Upper  Silurian,  although  Lower  Silurian  and  Lower 
Devonian  beds  may  occur. 
Matthew,27  in  1865,  correlates  the  Portland  series,  which  includes 
limestone,  syenite,  gneiss,  conglomerate,  slate,  and  graphitic  shale,  with 
the  Lauren tian,  first,  because  of  its  lithological  characteristics,  and 
second,  because  it  is  unconformably  overlain  by  great  thicknesses  of 
deposits  similar  to  the  Huronian  series  of  Canada.  The  Coldbrook 
Huronian  group  is  conformable  with  the  Lower  Silurian  St.  John  beds, 
although  there  is  a  marked  contrast  between  the  formations,  the  former 
containing  conglomerates  and  volcanic  products,  but  the  latter  none. 
Hind,28  in  1865,  in  a  geological  sketch  of  the  province  of  New  Bruns- 
wick, finds  no  rocks  older  than  the  Lower  Silurian.  The  belts  of  gran- 
ite are  regarded  as  of  Devonian  age,  being  apparently  thrust  up  through 
the  Lower  Silurian  and  Devonian  strata  before  the  beginning  of  the 
Carboniferous  epoch.  The  Quebec  group  includes  gneiss,  anorthosite, 
mica-schist,  hornblende  rocks,  diorite,  various  schists,  and  other  crys- 
talline rocks. 
Matthew  and  Bailey,29  in  1870,  divide  the  metamorphic  rocks  of 
New  Brunswick  and  Maine  into,  first,  a  Laurentian  series,  which  con- 
sists of  gneiss,  often  granitoid  in  aspect,  including  (1)  crystalline  lime- 
stone and  inter  stratified  beds  of  quartzite  and  diorite,  (2)  a  Labia*  lo- 
rian  or  Upper  Laurentian  series,  which  consists  of  feldspar  rock 
associated  with  hypersthene  and  magnetite;  and,  second,  a  Cambrian  or 
Huronian  series.     The  granites  of  St.  Johns  river  are  of  Devonian  age. 
Bailey  and  Matthew,30  in  1872;  find  the  Laurentian  system  to  have 
a  rather  widespread  distribution.     The  rocks  are  placed  in  the  Lau- 
