﻿CRUSTACEA. 
  24 
  1 
  

  

  ambulatory 
  legs. 
  The 
  ej-e-peduncles 
  are 
  very 
  short 
  and 
  thick, 
  with 
  

   very 
  large 
  corneas 
  ; 
  the 
  antennules 
  are 
  transverse 
  ; 
  the 
  basal 
  joint 
  

   of 
  the 
  antennae 
  is 
  slender, 
  and 
  although 
  longer 
  than 
  the 
  two 
  fol- 
  

   lowing 
  joints, 
  does,not 
  reach 
  to 
  the 
  subfrontal 
  process 
  ; 
  the 
  ischium- 
  

   joint 
  of 
  the 
  outer 
  maxillipedes 
  is 
  rather 
  short 
  and 
  broad, 
  but 
  longer 
  

   than 
  the 
  next 
  joint 
  and 
  longitudinally 
  sulcated 
  ; 
  the 
  merus 
  is 
  

   quadrate, 
  the 
  slender 
  exognath 
  reaches 
  to 
  the 
  distal 
  end 
  of 
  the 
  

   merus. 
  The 
  chelipedes 
  are 
  subequal 
  and 
  of 
  moderate 
  size, 
  and, 
  as 
  

   already 
  stated, 
  pubescent 
  ; 
  the 
  merus 
  or 
  arm 
  is 
  trigonous 
  and 
  has 
  a 
  

   tooth 
  near 
  the 
  distal 
  end 
  of 
  its 
  upper 
  margin 
  ; 
  the 
  carpus 
  is 
  armed 
  

   with 
  a 
  strong 
  spine 
  on 
  its 
  inner 
  surface 
  ; 
  palm 
  somewhat 
  shorter 
  

   than 
  the 
  fingers, 
  the 
  margins 
  not 
  cristated, 
  the 
  fingers 
  regularly 
  

   denticulated 
  and 
  meeting 
  along 
  their 
  inner 
  margins 
  and 
  acute 
  at 
  

   their 
  apices, 
  but 
  without 
  a 
  tuft 
  of 
  hair 
  at 
  base. 
  The 
  ambulatory 
  

   legs 
  are 
  slender, 
  with 
  the 
  joints 
  somewhat 
  compressed 
  and 
  scantily 
  

   pubescent 
  ; 
  the 
  margins 
  of 
  the 
  penultimate 
  and 
  terminal 
  joints 
  of 
  the 
  

   last 
  pair 
  of 
  legs 
  are 
  fringed 
  with 
  long 
  hairs, 
  but 
  the 
  terminal 
  joint 
  

   of 
  the 
  last 
  pair 
  of 
  legs 
  is 
  styliform 
  and 
  not 
  dilated. 
  The 
  bases 
  of 
  

   the 
  male 
  verges 
  lie 
  in 
  wide 
  open 
  canalicuU 
  of 
  the 
  sternum, 
  and 
  these 
  

   organs 
  (in 
  the 
  single 
  specimen 
  examined, 
  which 
  is 
  probably 
  not 
  

   adult) 
  are 
  nearly 
  straight. 
  Colour 
  (in 
  spirit) 
  whitish. 
  Length 
  of 
  

   the 
  carajiace 
  of 
  the 
  male 
  3| 
  lines 
  (nearly 
  8 
  millim.), 
  breadth 
  4| 
  lines 
  

   (nearly 
  lU 
  millim.); 
  length 
  of 
  chelipede 
  when 
  fully 
  extended 
  nearly 
  

   I 
  inch 
  (12 
  millim.), 
  of 
  second 
  ambulatory 
  leg 
  about 
  7g 
  lines 
  

   (16 
  millim.). 
  

  

  Two 
  specimens, 
  one 
  a 
  male 
  and 
  the 
  other 
  sterile, 
  were 
  collected 
  

   in 
  the 
  Arafura 
  Sea, 
  32-36 
  fms. 
  (No. 
  160). 
  

  

  Haswell's 
  types 
  were 
  from 
  Holborn 
  Island, 
  Port 
  Denison 
  (20 
  fms.). 
  

   As, 
  in 
  his 
  brief 
  description, 
  he 
  does 
  not 
  mention 
  the 
  pubescence 
  of 
  

   the 
  carapace, 
  and 
  as 
  his 
  specimens 
  differ 
  in 
  coloration, 
  it 
  is 
  pos- 
  

   sible 
  that 
  ours 
  are 
  distinct 
  ; 
  and 
  if 
  so, 
  I 
  would 
  propose 
  to 
  designate 
  

   them 
  P. 
  hasivelli. 
  

  

  Garcinoplax 
  vestitus*, 
  as 
  figured 
  by 
  De 
  Haan, 
  differs 
  in 
  its 
  some- 
  

   what 
  narrower 
  front, 
  in 
  the 
  shorter, 
  less 
  prominent 
  third 
  antero-lateral 
  

   spine, 
  more 
  quadrate 
  carapace, 
  less 
  compressed 
  chelipedes, 
  and 
  in 
  the 
  

   absence 
  of 
  long 
  cilia 
  from 
  the 
  terminal 
  joint 
  of 
  the 
  dactyli 
  of 
  the 
  

   fifth 
  ambulatory 
  legs. 
  

  

  The 
  distinctions 
  between 
  the 
  genera 
  Carcmoplax, 
  Eucrate, 
  and 
  

   Pilumnoplax 
  of 
  Stimpsonf 
  are 
  very 
  slight, 
  and 
  a 
  revision 
  of 
  the 
  

   group 
  is 
  urgently 
  needed. 
  If, 
  as 
  is 
  probable, 
  all 
  three 
  genera 
  should 
  

   have 
  to 
  be 
  united, 
  the 
  designation 
  Pseudorlwmhila 
  will, 
  I 
  think, 
  take 
  

   precedence, 
  since 
  De 
  Haan's 
  name 
  Eucrate 
  differs 
  by 
  a 
  letter 
  only 
  

   from 
  the 
  earlier 
  name 
  Eucratea, 
  and 
  Curtonotus 
  had 
  previously 
  been 
  

   used 
  in 
  the 
  Coleoptera. 
  

  

  * 
  Cancer 
  {Curtonotus) 
  vestitus, 
  DeHaan, 
  in 
  Siebold, 
  Fauna 
  Japonica, 
  Crust, 
  

   p. 
  51, 
  pi. 
  V. 
  fig. 
  3(1835). 
  

  

  t 
  Proc. 
  Acad. 
  Nat. 
  Sci. 
  Philad. 
  p. 
  93 
  (1858). 
  

  

  