﻿386 
  Dr. 
  C. 
  Chilton 
  on 
  

  

  seems 
  to 
  me 
  to 
  be 
  quite 
  as 
  unguiform 
  as 
  in 
  most 
  of 
  the 
  

   specimens 
  ot* 
  L. 
  lignorum 
  tliat 
  I 
  liave 
  examined, 
  

  

  A 
  comparison 
  of 
  the 
  uropoda 
  of 
  tiie 
  species 
  at 
  my 
  disposal 
  

   shows 
  that 
  the 
  structure 
  is 
  essentially 
  the 
  same 
  throughout 
  

   and 
  that 
  the 
  resemblances 
  are 
  very 
  close, 
  closer 
  than 
  miglit 
  

   be 
  anticipated 
  from 
  a 
  comparison 
  of 
  the 
  figures 
  given 
  by 
  

   different 
  authors. 
  In 
  all 
  three 
  the 
  peduncle 
  bears 
  on 
  the 
  

   under 
  surface, 
  at 
  some 
  little 
  distance 
  from 
  the 
  outer 
  margin, 
  

   a 
  longitudinal 
  row 
  of 
  long, 
  finely 
  plumose 
  hairs; 
  other 
  hairs 
  

   of 
  more 
  unequal 
  length 
  fringe 
  the 
  actual 
  margin. 
  The 
  end 
  

   of 
  the 
  peduncle 
  is 
  produced 
  on 
  the 
  underside 
  into 
  a 
  small 
  

   subacute 
  triangular 
  process 
  between 
  the 
  bases 
  of 
  the 
  rami. 
  

   The 
  inner 
  ramus 
  is 
  much 
  the 
  longer 
  and 
  bears 
  at 
  the 
  

   extremity, 
  which 
  is 
  usually 
  truncate, 
  a 
  tuft 
  of 
  long 
  seta?, 
  

   about 
  as 
  long 
  as 
  the 
  ramus 
  itself; 
  other 
  setos 
  may 
  be 
  present 
  

   on 
  the 
  outer 
  margin, 
  but 
  the 
  inner 
  margin 
  seems 
  in 
  all 
  cases 
  

   almost 
  free 
  from 
  setse. 
  The 
  inner 
  ramus 
  is 
  short 
  ; 
  it 
  curves 
  

   outwards 
  and 
  ends 
  in 
  a 
  nail, 
  at 
  the 
  base 
  of 
  which^ 
  on 
  the 
  

   concave 
  side, 
  is 
  a 
  tuft 
  of 
  about 
  three 
  seta? 
  which 
  reach 
  beyond 
  

   the 
  end 
  of 
  the 
  nail. 
  

  

  In 
  L. 
  lignorum 
  the 
  outer 
  margin 
  of 
  the 
  peduncle 
  usually 
  

   bears 
  a 
  number 
  of 
  small 
  tubercles 
  or 
  small 
  blunt 
  spines. 
  I 
  

   have, 
  however, 
  failed 
  to 
  find 
  these 
  in 
  some 
  of 
  the 
  Auckland 
  

   specimens, 
  in 
  which 
  the 
  outer 
  margin 
  is 
  slightly 
  roughened 
  

   only 
  ; 
  in 
  these 
  specimens 
  the 
  uropod 
  is 
  hardly 
  distinguishable 
  

   from 
  that 
  of 
  Z/. 
  segnis 
  (compare 
  hgs. 
  5 
  and 
  7). 
  

  

  In 
  the 
  specimens 
  from 
  South 
  Georgia, 
  which, 
  I 
  have 
  no 
  

   doubt, 
  must 
  be 
  referred 
  to 
  L. 
  aniarctica, 
  Pfefler, 
  the 
  outer 
  

   margin 
  of 
  the 
  {)eduncle 
  (fig. 
  8) 
  show^s 
  slight 
  evidence 
  of 
  

   tuberculation 
  : 
  both 
  rami 
  are 
  short, 
  though 
  not 
  quite 
  so 
  short 
  

   as 
  is 
  shown 
  in 
  Pfeffer's 
  figure, 
  taken 
  from 
  South 
  Georgia 
  

   specimens, 
  and 
  in 
  one 
  specimen, 
  a 
  small 
  one, 
  it 
  has 
  a 
  nail 
  at 
  

   the 
  end 
  quite 
  similar 
  to 
  that 
  in 
  L. 
  lignorum, 
  though 
  smaller. 
  

   In 
  L. 
  pfefferi 
  the 
  figure 
  given 
  by 
  Stebbing 
  shows 
  that 
  the 
  

   peduncle 
  is 
  the 
  s;ime 
  as 
  that 
  in 
  L. 
  lignorum 
  or 
  L. 
  segnis, 
  and 
  

   it 
  is 
  probable 
  that 
  the 
  whole 
  uropod 
  of 
  X. 
  ^y<'^e?"« 
  is 
  practi- 
  

   cally 
  the 
  same 
  as 
  in 
  these 
  two 
  species. 
  The 
  uropoda 
  of 
  

   L. 
  andreiosi, 
  as 
  drawn 
  by 
  (*alman, 
  have 
  a 
  short 
  peduncle 
  and 
  

   look 
  rather 
  different 
  from 
  those 
  of 
  the 
  other 
  species, 
  but 
  his 
  

   figure 
  is 
  too 
  small 
  to 
  show- 
  the 
  details 
  referred 
  to 
  above. 
  

  

  From 
  the 
  foregoing 
  account 
  it 
  will 
  be 
  seen 
  that 
  there 
  is 
  a 
  

   very 
  great 
  resemblance 
  between 
  all 
  the 
  species, 
  both 
  in 
  

   general 
  appearance 
  and 
  also 
  in 
  more 
  minute 
  characters 
  of 
  the 
  

   various 
  appendages 
  ; 
  they 
  constitute 
  a 
  well-marked 
  genus, 
  

   which 
  occupies 
  an 
  isolated 
  position 
  under 
  the 
  Sphseromidse. 
  

  

  