﻿662 
  COLLECTIONS 
  PEOM 
  THE 
  WESTEEN 
  INDIAN 
  OCEAN. 
  

  

  Islands, 
  and 
  may 
  be 
  identical 
  with 
  it 
  ; 
  but 
  differs 
  from 
  his 
  brief 
  de- 
  

   scription 
  in 
  some 
  minor 
  points, 
  e.g. 
  in 
  the 
  absence 
  of 
  the 
  smaU 
  

   spiuules 
  at 
  the 
  base 
  of 
  the 
  third 
  and 
  fourth 
  legs. 
  

  

  4. 
  Alpheus 
  minor, 
  var. 
  neptunus, 
  Dana. 
  

  

  Specimens 
  of 
  this 
  species, 
  whose 
  synonyms 
  and 
  distribution 
  have 
  

   been 
  referred 
  to 
  at 
  p. 
  288 
  of 
  this 
  E-eport, 
  are 
  in 
  the 
  collection 
  from 
  

   Darros 
  Island, 
  22 
  fms. 
  (No. 
  185), 
  He 
  des 
  Noufs, 
  15 
  fms. 
  (No. 
  187), 
  

   and 
  Glorioso 
  Islands, 
  7-10 
  fms. 
  (No. 
  219). 
  

  

  5. 
  Pontonia? 
  brevirostris. 
  (Plate 
  LI. 
  fig. 
  B.) 
  

  

  The 
  body 
  of 
  this 
  species 
  is 
  shaped 
  nearly 
  as 
  in 
  P. 
  tridacnm 
  (Peters). 
  

   The 
  rostrum 
  is 
  very 
  small, 
  not 
  at 
  all 
  laterally 
  compressed 
  ; 
  viewed 
  

   dorsally 
  it 
  is 
  triangular 
  and 
  acute, 
  and 
  scarcely 
  prolonged 
  beyond 
  

   the 
  bases 
  of 
  the 
  eye-peduncles 
  ; 
  the 
  anterior 
  margin 
  of 
  the 
  carapace, 
  

   near 
  to 
  the 
  antero-lateral 
  angles, 
  is 
  armed 
  with 
  a 
  spine 
  ; 
  the 
  lateral 
  

   margins 
  of 
  the 
  second 
  to 
  fifth 
  postabdominal 
  segments 
  are 
  obtusely 
  

   rounded, 
  those 
  of 
  the 
  sixth 
  segment 
  posteriorly 
  spiniform 
  and 
  acute 
  ; 
  

   the 
  terminal 
  segment 
  is 
  subtriangulate, 
  with 
  the 
  apex 
  subacute 
  

   (broader 
  and 
  more 
  rounded 
  in 
  the 
  adult 
  female), 
  and 
  bears 
  on 
  its 
  

   dorsal 
  surface 
  two 
  strong 
  spines 
  near 
  to 
  each 
  lateral 
  margin. 
  The 
  

   eye-peduncles 
  are 
  subcylindrical, 
  thick, 
  and 
  project 
  laterally. 
  The 
  

   first 
  exposed 
  joint 
  of 
  the 
  anteunulary 
  peduncles 
  is 
  flattened 
  and 
  con- 
  

   siderably 
  dilated, 
  and 
  has 
  two 
  spines 
  on 
  its 
  outer 
  margin, 
  of 
  which 
  

   one 
  is 
  at 
  the 
  extcro-distal 
  angle 
  of 
  the 
  joint 
  ; 
  the 
  next 
  joint 
  is 
  very 
  

   short, 
  the 
  terminal 
  joint 
  longer 
  ; 
  the 
  outermost 
  of 
  the 
  two 
  short 
  

   flagella 
  is 
  thickened 
  and 
  shortly 
  bipartite. 
  The 
  antennie 
  are 
  in- 
  

   serted 
  beneath 
  and 
  outside 
  of 
  the 
  antennnles, 
  and 
  their 
  short 
  

   peduncles 
  in 
  a 
  dorsal 
  view 
  are 
  hidden 
  by 
  the 
  antennal 
  scales, 
  which 
  

   are 
  large, 
  ovate, 
  and 
  distally 
  ciliated, 
  and 
  prolonged 
  beyond 
  the 
  

   distal 
  end 
  of 
  the 
  peduncles 
  and 
  the 
  antennnles. 
  The 
  slender 
  man- 
  

   dibles 
  arc 
  without 
  a 
  palpus 
  ; 
  the 
  outer 
  maxillipedes 
  are 
  subpediform, 
  

   with 
  the 
  antepenultimate 
  joints 
  but 
  slightly 
  thicker 
  and 
  a 
  little 
  

   longer 
  than 
  the 
  two 
  terminal 
  joints 
  taken 
  together. 
  The 
  anterior 
  

   legs 
  are 
  slender 
  and 
  unarmed, 
  with 
  merus 
  and 
  carpus 
  of 
  about 
  equal 
  

   length, 
  and 
  each 
  about 
  as 
  long 
  as 
  the 
  palm 
  and 
  fingers 
  taken 
  together 
  ; 
  

   the 
  palm 
  is 
  not 
  dilated, 
  and 
  the 
  fingers 
  are 
  not 
  denticulated 
  on 
  their 
  

   inner 
  margins. 
  The 
  second 
  legs 
  (in 
  the 
  specimens 
  examined) 
  are 
  

   but 
  moderately 
  thickened 
  and 
  of 
  nearly 
  equal 
  size 
  ; 
  ischium, 
  merus, 
  

   and 
  carpus 
  of 
  about 
  equal 
  length, 
  but 
  the 
  carpus 
  somewhat 
  thicker 
  ; 
  

   palm 
  longer 
  than 
  the 
  carpus, 
  smooth 
  and 
  rounded, 
  scarcely 
  com- 
  

   pressed 
  ; 
  fingers 
  about 
  as 
  long 
  as 
  palm, 
  meeting 
  along 
  their 
  inner 
  

   margins, 
  which 
  are 
  not 
  denticulated. 
  Ambulatory 
  legs 
  slender, 
  

   with 
  the 
  penultimate 
  joints 
  about 
  twice 
  as 
  long 
  as 
  the 
  preceding 
  ; 
  

   dactyli 
  styliform 
  and 
  acute. 
  The 
  rami 
  of 
  the 
  uropoda 
  are 
  ovate 
  and 
  

   ciliated, 
  and 
  the 
  outermost 
  has 
  a 
  small 
  spinule 
  near 
  to 
  the 
  distal 
  end 
  

   of 
  its 
  outer 
  margin. 
  Colour 
  (in 
  spiritj 
  reddish 
  yellow. 
  The 
  exact 
  

   dimensions 
  of 
  the 
  larger 
  specimen, 
  owing 
  to 
  its 
  imperfect 
  condition, 
  

  

  