Io8  PROCEEDINGS  OF  THE  GEOLOGICAL  SOCIETY.  [May  1893. 
accumulation  of  Radiolarian  oozes.  Consequently,  we  are  not  bound 
to  believe  that  the  Tripoli  or  Polycystine  marls  of  the  Mediter¬ 
ranean  coasts  and  islands,  for  instance,  were  upheaved  from  any 
very  extraordinary  depths.  As  a  case  in  point,  I  may  mention  the 
deposit  of  Oran,  stated  by  Haeckel  to  be  a  pure  Radiolarian  ooze 
very  similar  to  that  now  found  in  the  Central  Pacific.1  Without  doubt 
both  the  Mediterranean  and  the  Caribbean  Sea  have  been  in  times  past, 
and  still  are,  regions  subject  to  a  considerable  amount  of  vertical 
oscillation.  Indeed,  the  analogies  which  these  two  seas  present  are 
very  remarkable.  Each  of  them  is  a  deep  and  irregular  depression 
enclosed  within  a  continental  area.  The  Caribbean  Sea,  it  is  true, 
lies  more  open  to  the  ocean,  which  possesses  many  superficial 
entrances  through  the  submarine  continental  slope  connecting  the 
two  Americas.  Barbados  is  on  the  very  edge  of  this  slope,  perched 
like  an  outwork  on  the  top  of  a  gigantic  wall,  the  greater  part  of 
which  is  submerged.  Thus  its  position  perhaps  renders  it  liable  to 
vertical  movements  of  considerable  intensity. 
As  regards  the  age  of  the  Barbadian  Earths,  the  evidence  from 
organic  remains  seems  to  be  somewhat  contradictory.  According 
to  Haeckel,  as  quoted  by  the  Authors,  about  25  per  cent,  of  the  Radio- 
laria  found  in  the  Barbadian  Earths  are  likewise  known  from  the 
recent  ooze.  Even  supposing  that  the  investigation  of  the  recent 
Radiolaria  is  somewhat  incomplete,  such  a  percentage  almost  points 
to  a  Miocene  age,  and  this  seems  to  have  been  the  view  of  Haeckel 
himself.  It  is  also  Mr.  Lechmere  Guppy’s  view  as  to  the  age  of  the 
Radiolarian  Beds  of  Trinidad.  On  the  other  hand,  the  evidence  as 
regards  the  Eoraminifera  is  somewhat  uncertain.  The  late  Mr.  H.  B. 
Brady  remarked  that  there  was  still  much  to  learn  respecting  the 
Rhizopod  fauna  of  these  deposits,  before  any  very  satisfactory  con¬ 
clusion  could  be  drawn  as  to  their  geological  age  or  the  depth  of 
water  at  which  they  were  formed.  Still,  he  had  little  hesitation  in 
concluding  that  of  the  81  species  of  Eoraminifera  enumerated  about 
72  are  certainly  recent  forms,  and  half  the  remainder  probably  so. 
He  further  adds  that  an  investigation  of  the  Microzoa  of  a  large 
series  of  soft  deposits  from  various  islands  of  the  South  Pacific  has 
yielded  a  very  similar  result,  and  he  agrees  with  Hr.  H.  B.  Guppy, 
who  has  assigned  to  them  a  post-Tertiary  date. 
It  may  be  as  well  to  mention  here,  by  way  of  parenthesis,  that 
the  *  Soapstone  '  of  Eiji,  described  by  Mr.  Brady  in  the  Quarterly 
Journal,  rests  on  a  sort  of  Coral-limestone  instead  of  being  covered 
•  1  Op.  cit.  p.  clxvi. 
