﻿282 
  COLLECTIONS 
  PKOM 
  MELANESIA. 
  

  

  Seven 
  specimens 
  were 
  collected 
  at 
  Port 
  Darwin 
  at 
  12 
  fms 
  (in- 
  

   cluding 
  both 
  sexes) 
  ; 
  two 
  or 
  three 
  are 
  females 
  with 
  ova. 
  In 
  the 
  

   last 
  collection 
  from 
  H.M.S. 
  ' 
  Alert 
  ' 
  specimens 
  from 
  Singapore 
  

   are 
  apparently 
  not 
  specifically 
  distinguishable, 
  although 
  presenting 
  

   some 
  slight 
  distinctions. 
  

  

  From 
  Oebiopsis 
  nitidus, 
  A. 
  M.-Edwards 
  *, 
  from 
  the 
  Cape 
  Verds 
  

   (the 
  type 
  of 
  the 
  genus), 
  this 
  species 
  is 
  distinguished 
  by 
  the 
  somewhat 
  

   different 
  form 
  of 
  the 
  rostrum, 
  the 
  existence 
  of 
  a 
  spine 
  on 
  the 
  

   carpus 
  of 
  the 
  chclipedes, 
  the 
  much 
  shorter 
  antennulary 
  and 
  antennal 
  

   peduncles, 
  &g. 
  

  

  A 
  male 
  from 
  Freraantle, 
  S.W. 
  Australia 
  {Dr. 
  J. 
  S. 
  Bowerhanlc), 
  

   differs 
  in 
  the 
  form 
  of 
  the 
  rostrum, 
  which 
  is 
  anteriorly 
  deflexed 
  ; 
  its 
  

   margins 
  armed 
  with 
  ten 
  spines 
  in 
  front 
  of 
  the 
  first 
  of 
  the 
  denticules 
  

   of 
  the 
  sides 
  of 
  the 
  head 
  ; 
  of 
  these, 
  four 
  (of 
  which 
  two 
  are 
  longer) 
  are 
  

   arranged 
  in 
  a 
  semicircle 
  in 
  front, 
  and 
  three, 
  posterior 
  to 
  them, 
  on 
  

   each 
  side. 
  I 
  would 
  propose 
  to 
  designate 
  this, 
  if 
  specifically 
  distinct, 
  

   G. 
  bowerbanJcii. 
  

  

  The 
  genus 
  Gehiopsis 
  scarcely 
  differs 
  from. 
  Gebia, 
  except 
  in 
  the 
  

   greater 
  development 
  of 
  the 
  lower 
  finger 
  of 
  the 
  chclipedes 
  (which 
  

   thus 
  are 
  perfectly 
  chelate), 
  and 
  is 
  probably 
  to 
  be 
  regarded 
  as 
  a 
  sub- 
  

  

  3. 
  Axius 
  plectrorhynclius, 
  StraJd. 
  

  

  I 
  am 
  somewhat 
  uncertain 
  of 
  the 
  identity 
  of 
  the 
  specimen 
  in 
  the 
  

   ' 
  Alert 
  ' 
  collection 
  with 
  Strahl's 
  type 
  from 
  Luzon, 
  and 
  therefore 
  

   subjoin 
  the 
  following 
  description 
  : 
  — 
  

  

  The 
  carapace 
  and 
  postabdomen 
  are 
  somewhat 
  membranaceous 
  in 
  

   texture, 
  as 
  in 
  most 
  species 
  of 
  the 
  genus. 
  The 
  cephalothorax 
  is 
  ver- 
  

   tically 
  deep 
  and 
  laterally 
  compressed 
  ; 
  the 
  carapace 
  is 
  smooth, 
  

   without 
  spines, 
  and 
  has 
  the 
  cervical 
  suture 
  distinctly 
  marked. 
  The 
  

   rostrum 
  is 
  prominent 
  and 
  narrow, 
  concave 
  above 
  between 
  the 
  eyes 
  ; 
  

   it 
  is 
  produced 
  somewhat 
  behind 
  them, 
  and 
  is 
  armed 
  on 
  the 
  lateral 
  

   margins 
  with 
  five 
  or 
  six 
  teeth 
  ; 
  at 
  the 
  base 
  of 
  the 
  rostrum, 
  in 
  the 
  

   median 
  dorsal 
  line, 
  the 
  carapace 
  rises 
  into 
  an 
  abrupt 
  prominence 
  ; 
  

   both 
  the 
  gastric 
  and 
  cardiac 
  regions 
  are 
  distinctly 
  defined. 
  The 
  

   postabdominal 
  segments 
  are 
  smooth, 
  the 
  first 
  very 
  small, 
  the 
  rest 
  

   nearly 
  of 
  equal 
  length 
  ; 
  the 
  lateral 
  margins 
  of 
  the 
  second 
  to 
  sixth 
  

   segments 
  are 
  nearly 
  straight, 
  entire, 
  and 
  are 
  not 
  produced 
  into 
  spines 
  

   at 
  either 
  the 
  antero-lateral 
  or 
  poster 
  o 
  -lateral 
  angles 
  ; 
  the 
  terminal 
  

   segment 
  is 
  quadrate, 
  very 
  little 
  broader 
  than 
  long, 
  a 
  little 
  broader 
  

   in 
  its 
  proximal 
  than 
  in 
  its 
  distal 
  half, 
  and 
  has 
  its 
  posterior 
  margin 
  

   straight. 
  The 
  eyes 
  are 
  of 
  moderate 
  length 
  and 
  thickness, 
  and 
  have 
  

   distinct 
  black 
  corneas 
  ; 
  the 
  antennules 
  are 
  of 
  moderate 
  length, 
  their 
  

   antepenultimate 
  joints 
  longer 
  than 
  the 
  two 
  following, 
  which 
  are 
  

   subequal 
  ; 
  the 
  two 
  flagella 
  are 
  of 
  equal 
  thickness, 
  with 
  naked 
  joints. 
  

   The 
  antennae 
  are 
  shorter 
  than 
  the 
  animal, 
  the 
  antepenultimate 
  joint 
  

   of 
  the 
  peduncle 
  shorter 
  than 
  the 
  following, 
  and 
  armed 
  beneath 
  with 
  

   a 
  small 
  spinule 
  ; 
  the 
  penultimate 
  joint 
  longer 
  than 
  the 
  last 
  joint 
  ; 
  the 
  

  

  * 
  NouT. 
  Archiv. 
  Mus. 
  Hist. 
  Nat. 
  iv. 
  p. 
  fi3, 
  pi. 
  xviii. 
  figs. 
  4-7 
  (1868). 
  

  

  