﻿MIDDLE 
  PLEISTOCENE 
  GRAVEL 
  IN 
  LANCASHIRE. 
  39 
  

  

  The 
  annexed 
  list 
  enumerates 
  all 
  which 
  have 
  yet 
  been 
  identified. 
  

   The 
  names 
  are 
  given 
  according 
  to 
  the 
  British 
  Conchology 
  of 
  Mr. 
  

   Jeffreys. 
  

  

  In 
  addition 
  to 
  its 
  extent, 
  the 
  list 
  exhibits 
  several 
  points 
  of 
  interest, 
  

   and, 
  in 
  certain 
  characteristic 
  respects, 
  points 
  of 
  novelty 
  in 
  comparison 
  

   with 
  any 
  hitherto 
  published 
  lists 
  from 
  deposits 
  of 
  similar 
  age 
  in 
  

   Lancashire 
  or 
  England. 
  These 
  are 
  noted 
  in 
  the 
  sequel. 
  

  

  Except 
  where 
  otherwise 
  marked, 
  all 
  the 
  species 
  are 
  represented 
  by 
  

   small 
  much-worn 
  fragments 
  ; 
  but 
  the 
  occurrence 
  of 
  whole 
  and 
  of 
  

   comparatively 
  little-worn 
  shells 
  is 
  much 
  more 
  frequent 
  than 
  in 
  the 
  

   gravel 
  at 
  Blackpool 
  or 
  the 
  Liverpool 
  clays. 
  

  

  The 
  assemblage 
  of 
  species 
  as 
  a 
  whole 
  most 
  nearly 
  represents 
  that 
  

   of 
  the 
  Wexford 
  gravels, 
  of 
  which 
  it 
  may 
  not 
  be 
  too 
  wild 
  to 
  consider 
  

   this 
  deposit 
  a 
  Lancashire 
  representation, 
  if 
  not 
  extension. 
  The 
  

   present 
  occurrence 
  of 
  the 
  larger 
  univalves 
  (Aporrhais, 
  Purpura, 
  

   Murex, 
  Nassa, 
  and 
  Buccinum 
  undatum) 
  comparatively 
  little 
  worn 
  

   may 
  perhaps 
  indicate 
  that 
  this 
  bed 
  is 
  one 
  of 
  deposit 
  at 
  a 
  time 
  when 
  

   the 
  shells 
  found 
  in 
  it 
  were 
  living 
  at 
  no 
  great 
  distance, 
  and 
  probably 
  

   on 
  or 
  near 
  a 
  sea-beach 
  or 
  at 
  the 
  bottom 
  of 
  some 
  littoral 
  current. 
  

   In 
  this 
  respect 
  the 
  facies 
  of 
  the 
  collection 
  differs 
  from 
  that 
  of 
  similar 
  

   representations 
  from 
  the 
  Blackpool 
  or 
  Liverpool 
  beds, 
  and 
  resembles 
  

   rather 
  those 
  from 
  Moel 
  Tryfaen 
  and 
  Macclesfield. 
  One 
  might 
  almost 
  

   conjecture 
  that 
  the 
  Blackpool 
  and 
  Liverpool 
  fossils 
  were 
  actually 
  

   those 
  of 
  some 
  Leyland 
  or 
  Macclesfield 
  shores, 
  further 
  worn 
  and 
  

   widely 
  redistributed 
  by 
  the 
  waves 
  and 
  currents 
  of 
  a 
  retreating 
  

   ocean. 
  

  

  The 
  list, 
  although 
  containing 
  a 
  few 
  names 
  of 
  species 
  of 
  a 
  northern 
  

   character 
  (Astarte 
  an&Fusus), 
  contains 
  also 
  several 
  of 
  shells 
  of 
  markedly 
  

   southern 
  origin. 
  Venus 
  (Cytherea) 
  chione, 
  which 
  has 
  been 
  identified 
  

   at 
  Macclesfield 
  and 
  in 
  several 
  of 
  Mr. 
  Reade's 
  Liverpool 
  localities, 
  

   mayalmost 
  be 
  called 
  a 
  characteristic 
  fossil 
  at 
  Leyland. 
  Cardium 
  tuber- 
  

   culatum 
  (rusticum, 
  F. 
  & 
  H.) 
  occurs 
  not 
  unfrequently. 
  One 
  perfect 
  and 
  

   characteristic 
  hinge 
  of 
  Mactra 
  glauca 
  (helvacea, 
  F. 
  & 
  H.) 
  was 
  found. 
  

   All 
  these 
  are 
  essentially 
  southern 
  species. 
  The 
  only 
  shell 
  which 
  is 
  

   peculiarly 
  arctic 
  in 
  character 
  is 
  Fusus 
  (Trophori) 
  craticulatus, 
  Fabr., 
  a 
  

   species 
  now 
  living 
  in 
  Greenland, 
  of 
  which 
  one 
  fine 
  and 
  (for 
  drift) 
  fairly 
  

   fresh-looking 
  shell 
  has 
  been 
  found. 
  The 
  same 
  species 
  was 
  identified 
  

   at 
  Moel 
  Tryfaen. 
  

  

  With 
  this 
  last-named 
  exception 
  the 
  series 
  from 
  Leyland 
  must 
  be 
  

   described 
  as 
  very 
  similar 
  to 
  that 
  of 
  the 
  fauna 
  of 
  the 
  present 
  seas 
  

   along 
  the 
  western 
  shores 
  of 
  Britain. 
  A 
  curious 
  feature 
  of 
  it 
  is 
  

   the 
  occurrence 
  in 
  comparative 
  frequency 
  of 
  Fusus 
  antiquus, 
  var. 
  

   contrarius, 
  a 
  Wexford 
  fossil 
  and 
  common 
  in 
  the 
  Crag. 
  Another 
  is 
  

   the 
  similar 
  occurrence 
  of 
  limestone 
  pebbles 
  burrowed 
  by 
  Saxicava 
  

   rugosa, 
  and 
  in 
  some 
  cases 
  still 
  enclosing 
  the 
  two 
  valves 
  of 
  the 
  

   miner. 
  

  

  In 
  the 
  following 
  Table 
  v. 
  r. 
  means 
  that 
  1 
  to 
  3 
  specimens 
  have 
  

   occurred 
  ; 
  r. 
  3 
  to 
  10 
  ; 
  f., 
  frequent 
  ; 
  c, 
  common 
  ; 
  and 
  a., 
  abundant. 
  

  

  