Vol.  49.] 
ANTHRACOPTERA  AND  ANTHRACOMYA. 
257 
Anthracoptera  Browniana,  Salter. 
In  the  Trans,  of  the  Manchester  Geol.  Soc.  vol.  i.  pi.  v.  fig.  23,  in 
illustration  of  a  paper  by  Mr.  Binney,  Capt.  Brown  figured  a  specimen 
from  the  Pendleton  coal-pits,  but  without  naming  or  describing  it. 
However,  in  his  ‘Possil  Conchology,’  pl.lxviii.  fig.  9,  he  refigures  the 
specimen  and  appends  a  short  description.  The  figures  of  his  shell 
are  in  both  cases  of  unbroken  specimens,  but  I  cannot  say  anything 
further  as  to  their  correct  affinity.  When,  however,  Salter  published 
his  description  of  Anthracoptera  Browniana  (Geol.  Surv.  Mem., 
‘  Country  round  Wigan,’  2nd  ed.  p.  38,  fig.  3  a,  b)  he  figured  a  shell 
evidently,  judging  from  its  lines  of  growth,  a  complete  specimen, 
and  like  Brown’s  ;  but  he  changed  it  into  a  form  of  his  new  genus 
by  adding  parts  to  the  shell  where  the  shape  did  not  agree  with  his 
new  form. 
I  have  been  unable  to  see  in  any  museum,  or  to  collect,  forms  of 
shell  like  Brown’s  ;  but,  if  his  figure  be  correct,  they  probably  will 
be  more  accurately  referred  to  the  Posidonice ,  and  I  have  therefore 
not  recognized  Anthracoptera  Browniana  as  a  species  of  this  genus. 
I  have  redescribed  the  four  forms  originally  figured  by  Sowerby, 
though  I  should  be  very  loth  to  guarantee  the  absolute  separation  of 
these  four  species.  Probably,  had  I  been  describing  these  forms  for 
the  first  time,  I  should  have  created  only  two  species,  considering 
Anthracoptera  modiolaris  and  A.  quadrata  as  varying  forms  of  the 
one,  A.  triangularis  and  A.  carinata  of  the  other. 
I  have  been  unable  to  examine  Continental  and  American  types, 
which  I  have  given  as  synonyms,  except  from  plates  and  descrip¬ 
tions.  These,  however,  all  agree  very  closely  with  the  forms 
to  which  I  have  suggested  their  relationship.  This  reference  must 
be  regarded  as  only  tentative,  and  liable  to  be  modified  by  the  results 
of  further  investigations. 
Part  II. — The  Affinities  of  Anthracomta. 
Salter,  Geol.  Surv.  Mem.,  ‘  Iron  Ore3  of  South  Wales,’  p.  230. 
This  genus  was  established  by  Salter  in  1862  for  certain  shells 
which  had  been  described  by  Sowerby,  Trans.  Geol.  Soc.  ser.  2,  vol.  v., 
‘  Geology  of  Coalbrookdale,’  under  Unio,  and  as  Modiola  (Binney) 
and  Naiadites  (Dawson),  possessing  a  common  character  in  the 
periostracum,  which  he  considered  distinctive  of  the  family  Myadce, 
hence  the  name.  At  that  time,  however,  the  interiors  were  quite 
unknown,  and  the  correct  place  of  the  genus  could  only  be  guessed. 
Sir  J.  W.  Dawson  looked  upon  the  fossils  as  embryonic  forms  of 
£7mo,  from  the  microscopic  structure  of  the  shell,  which  he  describes 
as  presenting  an  internal  lamellar  and  subnacreous  layer,  a  thin  layer 
of  vertical  prismatic  shell,  and  periostracum.  The  ligament  is  ex¬ 
ternal,  there  are  no  hinge-teeth  or  byssal  sinus, 'and  he  did  not 
think  they  could  have  been  burrowers  (‘  Acadian  Geology,’  in  which 
are  figured  two  specimens  of  Anthracomya ,  A.  carhonaria ,  Dawson, 
non  Salter,  Quart.  Journ.  Geol.  Soc.  vol.  xix.  1863).  Another 
Q.  J.  G.  S.  No.  194. 
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