﻿G. 
  M. 
  Thomson. 
  — 
  New 
  Zealand 
  Crustacea. 
  246 
  

  

  Superior 
  pair 
  consisting 
  of 
  a 
  stout 
  peduncle, 
  bearing 
  a 
  crown 
  of 
  cilia 
  and 
  a 
  

   small 
  tuberculate 
  appendage, 
  with 
  a 
  flagelluni 
  of 
  two 
  long 
  slender 
  articula- 
  

   tions. 
  Inferior 
  antenna 
  four 
  -jointed 
  ; 
  first 
  three 
  joints 
  subequal, 
  with 
  

   numerous 
  cilia 
  ; 
  fourth 
  joint 
  very 
  short 
  and 
  furnished 
  with 
  a 
  few 
  long 
  hairs 
  

   at 
  its 
  extremity. 
  First 
  pair 
  of 
  gnathopoda 
  with 
  the 
  carpus 
  antero-iuferiorly 
  

   produced 
  to 
  an 
  acute 
  point 
  almost 
  to 
  the 
  extremity 
  of 
  the 
  propodos, 
  serrated 
  

   on 
  both 
  margins, 
  with 
  numerous 
  slender 
  spines 
  surrounding 
  it 
  near 
  the 
  

   base 
  of 
  the 
  propodos 
  ; 
  propodos 
  narrow-oblong, 
  serrated 
  on 
  both 
  margins, 
  

   with 
  a 
  small 
  dactylos 
  which 
  antagonises 
  with 
  the 
  extremity 
  of 
  the' 
  carpus. 
  

   Second 
  pair 
  of 
  gnathopoda 
  similar 
  to 
  first, 
  but 
  rather 
  larger, 
  and 
  with 
  the 
  

   carpus 
  produced 
  shghtly 
  beyond 
  the 
  extremity 
  of 
  the 
  propodos. 
  First 
  two 
  

   pairs 
  of 
  pereiopoda 
  with 
  the 
  basos 
  somewhat 
  dilated 
  ; 
  meros, 
  carpus 
  and 
  

   propodos 
  diminishing 
  uniformly 
  in 
  size 
  and 
  quite 
  smooth 
  ; 
  dactylos 
  very 
  

   small, 
  acute. 
  Third 
  pair 
  with 
  the 
  margin 
  of 
  the 
  basos 
  quite 
  smooth, 
  and 
  

   the 
  distal 
  extremity 
  sub-acute 
  ; 
  ischium 
  articulating 
  subapically 
  within 
  the 
  

   posterior 
  margin 
  ; 
  remaining 
  joints 
  about 
  half 
  as 
  long 
  us 
  the 
  basos 
  ; 
  meros 
  

   and 
  carpus 
  quite 
  smooth 
  ; 
  propodos 
  slender, 
  slightly 
  longer 
  than 
  the 
  pre- 
  

   ceding 
  joints, 
  and 
  serrated 
  on 
  the 
  posterior 
  margin 
  only. 
  Fourth 
  pair 
  of 
  

   pereiopoda 
  with 
  the 
  basos 
  posteriorly 
  arcuate 
  and 
  anteriorly 
  excavate, 
  

   rounded 
  at 
  the 
  extremity 
  ; 
  ischium 
  articulating 
  within 
  the 
  posterior 
  margin 
  

   near 
  the 
  centre; 
  remaining 
  joints 
  about 
  one-third 
  as 
  long 
  as 
  basos 
  ; 
  meros 
  

   very 
  small 
  ; 
  carpus 
  long 
  ; 
  propodos 
  half 
  its 
  length, 
  both 
  serrated 
  on 
  the 
  

   posterior 
  margins 
  ; 
  dactylos 
  long, 
  nearly 
  straight, 
  sub-acute. 
  Fifth 
  pan* 
  of 
  

   pereiopoda 
  membranous 
  ; 
  basos 
  curved 
  forward 
  nearly 
  to 
  a 
  right 
  angle 
  ; 
  

   remaining 
  joints 
  represented 
  by 
  a 
  small 
  tubercle. 
  Three 
  last 
  pairs 
  of 
  

   pleopoda 
  foliaceous 
  ; 
  ante-penultimate 
  paii" 
  having 
  a 
  short 
  peduncle, 
  the 
  

   rami 
  somewhat 
  unequal, 
  margins 
  smooth 
  ; 
  penultimate 
  pair 
  with 
  a 
  long 
  

   peduncle 
  and 
  rami 
  subequal, 
  outer 
  ramus 
  finely 
  serrate 
  on 
  its 
  outer 
  margin; 
  

   ultimate 
  pair 
  with 
  the 
  peduncle 
  rather 
  short 
  and 
  rami 
  very 
  unequal 
  ; 
  

   external 
  ramus 
  minute, 
  lanceolate, 
  with 
  smooth 
  margins 
  ; 
  internal 
  ramus 
  

   oblong, 
  obhque, 
  finely 
  serrate 
  on 
  the 
  distal 
  half 
  of 
  both 
  margins. 
  Telson 
  

   triangular, 
  obtusely 
  pointed. 
  

  

  Colour 
  yellow, 
  nearly 
  transparent, 
  with 
  small 
  red 
  spots. 
  Length 
  '5 
  

   inch. 
  Can 
  roll 
  itself 
  almost 
  into 
  a 
  ball. 
  

  

  Washed 
  up 
  on 
  the 
  Ocean 
  Beach 
  at 
  Dunedin. 
  

  

  I 
  have 
  named 
  this 
  sj)ecies 
  as 
  above, 
  from 
  the 
  fact 
  that 
  it 
  is 
  almost 
  inter- 
  

   mediate 
  between 
  the 
  only 
  two 
  species 
  hitherto 
  described 
  — 
  P. 
  rissoiniB, 
  Bate, 
  

   and 
  P. 
  serratus, 
  Bate. 
  

  

  Speuce 
  Bate 
  remarks 
  of 
  this 
  genus 
  : 
  — 
  "It 
  appears 
  to 
  me 
  to 
  be 
  not 
  

   improbable 
  that 
  Platyscelus 
  may 
  prove 
  to 
  be 
  the 
  female 
  of 
  Typhis 
  (Thyro^ms 
  J, 
  

   from 
  which 
  it 
  differs, 
  only 
  in 
  the 
  form 
  of 
  the 
  superior 
  and 
  length 
  of 
  the 
  

   inferior 
  antennse." 
  

  

  