Yol.  49.] 
AFFINITIES  OF  ANTHRACOPTERA  AND  ANTHRACOMYA.  249 
20.  On  the  Affinities  of  Anthracoptera  and  Anthracomya.  By 
Wheelton  Hind,  M. D.,  B.S.,  F.R.C.S.,  F.G.S.  (Head 
February  22nd,  1893.) 
[Plates  YIL,  VIII.,  IX.,  &  X.] 
Part  I. — The  Affinities  of  Anthracoptera. 
The  first  mention  of  these  shells  is  by  Sowerby  in  Prestwich’s 
memoir  on  the  geology  of  Coalbrookdale,  where  four  species  are 
figured — one  as  Modiola ,  a  second  as  Mytilus ,  and  the  other  two  as 
Avicida.  These  were  hesitatingly  referred  to  Myalina  or  Avicula  by 
Salter,  in  ‘  Iron  Ores  of  South  Wales,’  Mem.  Geol.  Surv.  1861,  where 
in  a  footnote  (p.  230)  he  hazards  the  conjecture  that  they  may  belong 
to  Anthracomya ,  a  genus  then  described  for  the  first  time  to  contain 
shells  previously  referred  to  Unio.  In  1862,  in  the  memoir  on  the 
4  Geology  of  the  Country  round  Wigan,’  he  proposed  the  name 
Anthracoptera  for  certain  shells  previously  described  and  figured  as 
Avicula,  Modiola ,  and  Myalina  ;  he  there  detailed  the  specific  cha¬ 
racters  and  gave  a  diagrammatic  woodcut  of  the  genus. 
In  the  Supplementary  Chapter  to  4  Acadian  Geology,’  1860,  Sir 
•J.  W.  Dawson  proposed  the  name  Naiadites  to  include  all  Coal 
Measure  shells  :  he  then  figured  no  shell  referable  to  this  genus, 
although  Salter,  in  his  paper  ‘  On  some  fossil  Crustacea  from  the 
Coal-measures  of  British  North  America,'  Quart.  Journ.  Geol.  Soc. 
vol.  xix.  (1863)  p.  79,  figured  a  shell,  Anthracoptera  carbonaria, 
evidently  correctly,  but  erroneously  identified  it  with  Dawson's  figure 
(fig.  42,  p.  204),  which  really  represents  an  Anthracomya.  Subse¬ 
quently,  in  the  2nd  edition,  in  1868,  Sir  J.  W.  Dawson  showed  that 
he  believed  JSfaiaclites  carbonaria  to  be  synonymous  with  Anthraco¬ 
ptera  carbonaria,  Salter,  and  Naiadites  lords  with  Anthracoptera  Icevis, 
the  figures  giveu  resembling  Anthracomya  rather  than  Anthracoptera. 
In  1852  Hyckholt  figured,  under  Mytilus ,  three  specimens  from 
the  neighbourhood  of  Mons.  These  doubtless  belong  to  the  genus 
under  discussion ;  and  Ludwig,  as  Dreissenict ,  describes  four  species 
from  the  Coal  Measures  of  Germany. 
Asipiionida  (integropallialia). 
Family  Mytilidhi 
Genus  Anthracoptera,  Salter. 
Syn.  Modiola ,  Sowerby, Trans.  Geol.  Soc.  ser.  2,  vol.  v.  pt.  3,  pi.  xxxix.  figs.  15-18. 
Mytilus,  ibid.  ibid. 
Avicula ,  ibid.  ibid  5 
Myalina ,  Salter,  Geol.  Surv.  Mem.,  ‘Iron  Ores  of  South  Wales,’  p.  230. 
Anthracoptera,  Salter,  Geol.  Surv.  Mem.,  ‘  Country  round  Wigan,’  1862. 
Mytilus,  Ryckholt,  ‘  Melanges  paleontologiques,’  1852. 
Dreissenia,  Ludwig,  ‘  Palreontographica,’  vol.  viii.  (1859-1861). 
