nan  Hisf.j  EASTERN    CANADA    AND    NEWFOUNDLAND.  245 
adjacent  to  the  sedimentary  rocks — are  better  explained  by  regarding 
the  granite  as  intrusive.  The  natural  explanation  of  the  rounded  bowl- 
ders remote  from  the  contacts  is  that  they  represent  partially  absorbed 
pieces  of  these  rocks.  The  evidence  given  by  Dawson  as  to  the  struc- 
tural relations  of  the  granite  and  the  manner  in  which  the  granite  fades 
off  into  the  slates,  mentioned  by  Faribault,  is  wholly  conclusive  as  to 
the  intrusive  origin  of  a  portion  of  the  granites.  The  relations  thus 
described  by  Faribault  are  precisely  like  those  which  obtain  between 
the  granites  and  intruded  metamorphosed  schists  in  the  Black  hills 
and  about  Rainy  lake  and  lake  of  the  Woods. 
While  it  is  thus  certain  that  large  areas  of  granite  and  felsite  are  in- 
trusives  of  later  age  than  the  rocks  which  are  certainly  of  clastic  ori- 
gin, it  does  not  follow  that  a  portion  of  the  felsites,  porphyritic  gneisses 
and  granites  are  not  of  earlier  age  than  any  of  the  plainly  clastic  rocks. 
It  is  of  interest  to  note  that  while  Dawson  insists  that  all  of  the 
granites  of  Nova  Scotia  proper  are  of  truly  Hypogene  origin  of  later 
age  than  the  sedimentaries,  that  he  suggests  that  it  is  not  improbable 
that  they  have  themselves  been  produced  by  the  actual  fusing  of  these 
sedimentaries.  This  hypothesis  is  the  same  as  that  proposed  by  Law- 
son  many  years  later  to  explain  analogous  phenomena  between  the 
granites  and  gneisses  and  the  associated  schists  and  elastics  of  Rainy 
lake  and  the  lake  of  the  Woods. 
In  considering  the  positions  and  successions  of  the  plainly  clastic 
rocks  of  cape  Breton  and  Nova  Scotia,  we  have  two  geological  prov- 
inces: the  first  including  northern  Nova  Scotia  and  cape  Breton,  which 
is  analogous  to  southern  New  Brunswick;  and,  second,  the  main  part 
of  Nova  Scotia,  south  of  the  line  running  from  Minas  basin  to  Cheda- 
bucto  bay. 
In  the  second  of  these  regions,  aside  from  the  granites,  the  only  area 
that  is  of  interest  in  connection  with  our  study  is  the  gold-bearing  At- 
lantic coast  series.  Dawson  in  1850  places  this  as  Lower  Silurian 
or  pre- Silurian.  Later,  m  his  Acadian  Geology,  it  is  classified  as 
Lower  Silurian,  although  it  is  stated  that  no  fossils  are  found  in  them. 
Later  it  was  placed  by  Faribault  as  Lower  Cambrian.  The  only 
evidence  cited  by  him  for  placing  it  in  the  fossiliferous  series  at  all 
is  the  presence  of  the  obscure  fossil  Eophyton,  discovered  by  Selwyn. 
Dawson  found  no  fossil  evidence  for  his  reference  of  this  series  to  the 
Silurian;  and  it  is  remarked  by  Silliman  that  immediately  overlying 
rocks  containing  fossils  have  never  been  found.  Although  Hind  in 
1870  says  that  the  fossiliferous  Upper  Silurian  conformably  overlies  the 
gold-bearing  series,  this  statement  has  been  found  nowhere  else  and 
subsequent  observers  have  not  repeated  it,  so  that  it  maybe  considered 
very  doubtful. 
It  is  then  clear  that  the  position  of  the  gold-bearing  slates  in  the 
Lower  Silurian  or  Lower  Cambrian  is  purely  provisional.  They  can 
only  be  considered  as  certainly  belonging  here  under  the  premise  that 
