Voi.  49.] 
OF  THE  SHERBORNE  DISTRICT. 
495 
only  locality  which  can  be  named  with  it ;  a  few  of  the  peculiar 
Sandford  Lane  species  have  been  obtained  from  there. 
The  few  inches  of  the  upper  part  of  the  bed  are  lithologically 
different,  and  yield  a  fauna  very  distinct  from  that  of  the  lower  part. 
By  the  fauna  it  is  possible  to  identify  the  horizon  of  this  part  of 
the  bed  over  a  wider  area  than  that  of  the  lower  part.  My  own 
impression  is  that  if  the  strata  were  more  developed,  it  would  be 
seen  that  the  species  which  lived  during  three  hemerae  are  contained 
in  the 4  Fossil  Bed  5  of  Sandford  Lane:  (a)  species  of  the  Sonninia 
propinquans- type,  (b)  Witchellia  and  allies,  (c)  species  of  the  ‘Bonn? 
Jissilobata-tj^e.  Not  unlikely  the  bed  below — No.  8 — ought  to  be 
added  to  this  lowest  division :  it  represents  something  later  than 
L  at  Bradford  Abbas. 
Nothing  is  more  remarkable  than  the  complete  change  of  fauna 
in  the  ‘  Fossil  Bed  9  of  Sandford  Lane,  compared  with  strata  of 
the  concavi  or  even  discitce  hemerae.  Not  a  single  species  of  the 
Hildoceratidce  is  found  in  the  ‘  Fossil  Bed  9  of  Sandford  Lane.  The 
Sonninince  dominate  the  bed  entirely — one  division  of  the  genus 
Witchellia  has,  in  its  most  retrogressive  types,  curiously  enough 
a  great  external  resemblance  to  the  last  survival  of  the  Rildo- 
ceratidce 1 — Hyperlioceras  ;  the  Oppelidce  are  fairly  numerous  individ¬ 
ually,  but  not  specifically ;  and  the  same  may  be  said  of  the 
Stephanoceratidce ,  but  not  of  Stejohanoceras.  In  the  lower  part  of 
the  bed  the  Sonninince  are  still  in  the  acmastic  stage,  but  their 
paracmastic  stage  is  certainly  pronounced  in  the  upper  part.  The 
Oppelidce ,  though  they  have  increased  in  numbers  somewhat  since 
the  concavi  hemera,  are  still  in  the  epacmastic  stage. 
The  4  Fossil  Bed  ?  of  Sandford  Lane  has  a  remarkably  level  top  ; 
and  there  is  a  considerable  geological  gap — the  missing  strata  being 
seen  at  Frogden  (Sect.  XY.,  p.  500).  All  the  strata  above  it  I 
consider  as  contemporaneous  with  the  4  Astarte- bed  r  of  Halfway 
House,  and  perhaps  in  part  with  the  4  Fossil  Bed  ’  of  that  locality — 
so  that  the  increase  of  deposition  is  very  great  in  comparison.  It 
may  be  noted  that  the  same  small  species  of  Aulacoihyris  as  that 
found  at  Louse  Hill  occurs  here ;  but  it  is  now  about  20  feet  above 
Lioceras  concavum ,  instead  of  about  20  inches ;  yet  there  is  abundant 
evidence  that  it  occupies  the  same  palaeontological  horizon. 
These  4  upper  beds,’  as  they  are  generally  called,  though  they  are 
by  no  means  contemporaneous  with  the  upper  beds  of  the  Bradford 
area,  as  has  usually  been  thought,  may  be  advantageously  studied 
in  the  following  sections  : — 
1  Poecilomorpkus  being  excluded  as  doubtful.  Dr.  Haug  (in  litt.)  considers 
this  genus  to  be  one  of  the  Sonninince. 
9 
L 
Q.  J.  G.  S.  No.  196. 
