The  Carboniferous  Hocks  at  Rush.  423 
and  are  occasionally  inverted.  The  highest  beds  seen  (Cyathaxonia- 
Beds)  are  correlated  with  the  Eastern  Grower  or  Oystermouth  Lime- 
stone of  the  South-Western  Province;  but  the  fauna  agrees  still  more 
closely,  and  is  identical,  with  that  of  the  highest  Avonian  beds  of  the 
Midlands  of  England,  at  Parkhill,  Wetton,  Thorpe  Cloud,  etc.  The 
disappearance  by  solution  of  a  considerable  thickness  of  limestone 
is  described. 
A  list  is  given  of  the  fossils  from  a  large  number  of  horizons  in 
the  Hush  Series  (which  is  divided  into  the  Zaplirentis-,  Mec/astoma-, 
and  CyatJiaxonia-~Beds),  as  well  as  of  the  fauna  of  the  Curkeen-Hill 
Limestone,  near  Loughshinny,  the  horizon  of  which  is  assigned  to 
the  Upper  Dibunopliyllum-Tione,  probably  below  the  Cyathaxonia- 
Beds. 
The  palccontological  section  deals  only  with  brachiopods  and 
corals.  In  that  part  which  deals  with  the  brachiopods  the  inter- 
relationship of  the  various  members  of  the  more  important  gentes 
is  discussed  in  considerable  detail.  In  the  part  which  is  devoted  to 
the  corals  a  new  subgenus  is  suggested,  and  four  new  species  are 
described. 
January  10th,  1906.— J.  E.  Marr,  Sc.D.,  F.R.S.,  President, 
in  the  Chair. 
The  following  communications  were  read  : — 
1.  'The  Clay-with-Flints  :  its  Origin  and  Distribution.'  By 
xVlfred  John  Jukes-Browne,  B.A.,  F.G.S. 
Until  recently  the  Clay-with-Flints  has  been  regarded  as  being,  in 
the  main,  a  residue  from  the  slow  solution  of  the  Chalk.  This  was 
the  explanation  proposed  by  Mr.  "W.  Whitaker  in  1864,  although  he 
admitted  that  the  deposit  included  some  material  derived  from  the 
Eocene.  Writing  in  1865,  Mr.  T.  Codrington  thought  that  an  over- 
lying stratum  of  clay  or  loam  was  essential  to  the  formation  of  Clay- 
with-Flints.  Lastly,  Charles  Darwin  in  1881  seems  to  have  taken 
it  for  granted  that  it  was  solely  a  residue  from  the  Chalk.  Of 
late  years,  the  opinion  has  been  growing  that  it  consists  very  largely 
of  material  derived  from  the  Eocene. 
The  present  paper  is  devoted  to  an  examination  of  the  facts, 
with  the  view  of  ascertaining  whether  the  Clay-with-Flints  could 
possibly  be  derived  from  the  Chalk,  or  whether  the  theoiy  of  its 
derivation  from  the  Eocene  is  confirmed  by  more  detailed  enquiry. 
The  author  first  describes  its  composition,  noting  that  unbroken 
flints  are  not  everywhere  abundant,  that  broken  angular  flints 
are  common,  and  green-coated  flints  are  not  rare  ;  finally,  that  if 
the  clay  is  washed  it  always  yields  a  rcsiduo  of  sand,  composed 
chiefly  of  rounded  quartz-grains  with  some  of  iron-oxide,  and  both 
apparently  derived  from  the  Eocene  sands. 
The  thickness  of  the  accumulation  is  next  discussed,  especially 
