98 
PROCEEDINGS  OF  THE  GEOLOGICAL  SOCIETY. 
[May  1893, 
Tertiary  Geology. 
Having  spent  so  much  time  over  papers  relating  to  Pleistocene 
Geology,  it  will  be  necessary  to  touch  but  briefly  on  matters  which 
otherwise  might  well  have  occupied  our  attention  at  greater  length. 
The  Tertiary  Geology  of  West  Surrey  and  East  Berks,  taken  per  se, 
is  mainly  of  local  interest,  but  any  attempt  based  on  palaeontological 
data  to  correlate  portions  of  the  London  and  Hampshire  Basins,  and 
so  pave  the  way,  if  possible,  for  a  more  uniform  nomenclature,  must 
be  regarded  from  a  wider  standpoint. 
Upper  Eocene . — Such  a  paper  was  presented  to  the  Society  by 
Messrs.  Gardner,  Keeping,  and  Monckton,  entitled  ‘  On  the  Upper 
Eocene,  comprising  the  Barton  and  Upper  Bagshot  Formations.’ 
The  primary  object  which  the  Authors  had  in  view  was  to  effect 
a  partial  revision  of  the  grouping  of  the  older  British  Tertiaries, 
in  consequence  of  the  introduction  of  the  Oligocene  into  our 
classification.  Unless,  as  they  observe,  the  considerable  literature 
relating  to  the  Bracklesham,  the  Calcaire  Grossier,  and  the 
Nummulitic  is  to  be  rendered  obsolete,  their  classification  as  Middle 
Eocene  must  be  preserved,  and  a  modified  Upper  Eocene  constructed 
out  of  the  Barton  Series.  Secondly,  then,  the  Barton  Series,  as 
developed  in  Hampshire,  is  to  a  certain  extent  remodelled,  with  an 
adequate  notice  of  its  very  abundant  fauna  :  and  thirdly,  it  is  shown 
by  way  of  correlation  that,  in  all  probability,  the  beds  hitherto 
known  as  the  Upper  Bagshot  Sands  in  the  London  area  correspond 
to  the  lower  portion  of  this  series,  i.  e.  to  the  Lower  Bartons. 
It  is  admitted  that  the  base  of  the  Barton  Series  is  not  sharply 
defined,  since  there  is  no  boundary-line  of  importance,  paleontological 
or  lithological.  Indeed,  if  the  section  at  Whitecliff  Bay,  which  the 
Authors  regard  as  the  most  perfect  in  all  the  Eocene  formation 
in  England,  had  been  the  original  or  type-section,  a  different 
arrangement,  we  are  told,  from  that  which  now  exists  might  have 
been  entertained.  Here  the  fauna  of  the  Lower  Brackleshams, 
with  its  giant  Kummulites,  Bullas,  and  Cowries,  and  its  wealth  of 
Corals,  differs  far  more  from  that  of  the  Upper  Brackleshams  than 
the  latter  does  from  that  of  the  Bartons.  Had  the  Barton  Series  been 
in  the  first  instance  described  from  the  Highcliff  section  in  Christ¬ 
church  Bay,  and  then  followed  from  west  to  east,  taking  first  Alum 
Bay  and  then  Whitecliff  Ba}q  the  entire  Upper  Bracklesham  Series 
would  have  found  a  place  in  it,  and  the  base-line  would  have  been 
drawn  where  a  decided  physical  change  is  manifest.  However,  the 
division  as  now  made  coincides  with  the  final  disappearance  of  several 
