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PROF.  T.  R.  JONES  ON  CYPRIDINA  RAISINI2E.  [May  1893, 
Cypridinci  Rctisinice,  sp.  nov. 
[Enlarged  4  diameters.] 
Note  on  a  Fossil  Cypridinad  from  the  South  of  the  Lleyn. 
By  Prof.  T.  Bupert  Jones,  F.R.S.,  F.G.S. 
The  two  counterparts  of  a  hsematitic  cast,  one  convex  and  one 
hollow,  in  the  bluish-grey  schistose  mudstone,  weathering  brown, 
are  too  rough  and  imperfect  in  surface  and  in  outline  to  give  quite 
satisfactory  evidence  of  the  little  organism  they  represent.  It 
appears,  however,  to  be  a  badly  preserved  ostracod  of  Cypridinad 
affinity,  having  a  suboval  or  obovate  body,  with  a  hook  and  notch 
at  the  anterior  end,  and  a  strong  caudal  process  posteriorly.  It 
measures  9  by  5  millim. 
Analogous  features  in  various 
degrees,  and  associated  with  other 
characteristics,  exist  in  Cypri- 
dina  Reynaudii ,  Milne-Edwards, 
C.  elongcita ,  Brady,  C.  Bciirclii, 
Brady,  C.  japonica ,  Brady,  and 
other  hooded  and  apiculate  mem¬ 
bers  of  the  genus ;  but  none  of 
these  have  the  hinder  end  tapering 
away  to  so  long  and  strong  a  point. 
A  fossil  form,  however,  from  the 
Carboniferous  series  of  Sicily, 
described  and  figured  by  Prof. 
G.  G.  Gemmellaro  ( Philomedes 
acanthoides ,  Gemm.,  Mem.  Soc.  Ital.  Sci.  ser.  3,  vol.  viii.  1890, 
p.  37,  pi.  v.  figs.  16  and  17),  is  very  similar,  but  is  too  attenuate, 
and  measures  6*5  by  3  millim. 
Having  a  sufficiently  distinctive  form,  this  little  fossil  may  be 
regarded  as  of  specific  value ;  and,  in  honour  of  Miss  C.  A.  Baisin, 
the  discoverer,  I  call  it  Cypridinci  Raisinice. 
As  far  as  I  remember,  the  oldest  Cypridinad  yet  published  is  the 
“  Cypridinci  ?  Internal  cast  of  a  right  valve,  mag.  about  4  diam. 
From  a  pebble  of  Palaeozoic  quartzite  1  in  the  Triassic  conglomerate 
of  Budleigh  Salterton,  Devon.”  Geol,  Mag.  for  1881,  pp.  337  and 
347,  pi.  ix.  fig.  7. 
EXPLANATION  OF  PLATE  I. 
Fig.  1.  Ferruginous  basalt,  from  the  cliff  at  Maen-melyn-lleyn.  Dolomite  is 
seen  by  polarized  light  to  replace  felspar,  and  to  form  rhombohedral 
crystals,  represented  in  the  drawing  by  spotted  rhomboids.  The 
groundmass  consists  of  felspar,  of  minute  crystals  (left  blank),  which 
are  probably  augite,  and  of  dark  granules  and  microlitks  of  opacite. 
(Magnified  30  diam.) 
Fig.  2.  Ferruginous  basalt,  from  the  beach  of  the  small  cove  north  of  Porth 
Oer.  This  slide  shows  the  bent  and  wavy  character,  and  somewhat 
spherulitic  arrangement,  of  the  felspar-microliths.  The  dark  granular 
deposit  is  opacite,  which  partially  separates  the  felspars  of  the 
groundmass.  Parts  of  two  amygdules  are  shown :  these  consist  of 
quartz  and  dolomite  or  ankerite.  (Magnified  30  diam.) 
1  Devonian  or  Lower  Silurian. 
