﻿NO. 
  1950. 
  CRUSTACEAN 
  PARASITES 
  OF 
  FISH 
  AND 
  CRABS— 
  WILSON. 
  215 
  

  

  three-quarters 
  as 
  large 
  as 
  the 
  terminal 
  claws 
  of 
  the 
  second 
  antennae, 
  

   slender, 
  and 
  curved 
  but 
  shghtly; 
  maxillae 
  reaching 
  well 
  beyond 
  the 
  

   end 
  of 
  the 
  short 
  and 
  wide 
  mouth 
  tube, 
  slender, 
  with 
  an 
  enlarged 
  and 
  

   bluntly 
  rounded 
  tip; 
  maxillipeds 
  small, 
  the 
  terminal 
  claw 
  weak 
  and 
  

   only 
  half 
  the 
  length 
  of 
  the 
  basal 
  joint. 
  Furca 
  proportionally 
  large, 
  

   the 
  basal 
  part 
  subquadrilateral 
  with 
  the 
  sides 
  slightly 
  reentrant, 
  the 
  

   rami 
  one-half 
  longer 
  than 
  the 
  base, 
  nearly 
  parallel, 
  with 
  flattened 
  

   spatulate 
  tips. 
  

  

  Claws 
  on 
  the 
  exopods 
  of 
  the 
  second 
  legs 
  long 
  and 
  slender; 
  rami 
  of 
  

   the 
  third 
  legs 
  small 
  and 
  well 
  separated; 
  fourth 
  legs 
  (including 
  their, 
  

   spines) 
  reachmg 
  nearly 
  to 
  the 
  posterior 
  margin 
  of 
  the 
  genital 
  segment, 
  

   but 
  slender, 
  with 
  a 
  short 
  spine 
  on 
  the 
  outer 
  margin 
  of 
  the 
  basal 
  joint 
  

   near 
  its 
  distal 
  end, 
  a 
  long 
  terminal 
  spine 
  at 
  the 
  tips 
  of 
  the 
  second 
  and 
  

   third 
  joints 
  and 
  two 
  on 
  the 
  terminal 
  joint, 
  of 
  which 
  the 
  inner 
  is 
  twice 
  

   the 
  length 
  of 
  the 
  outer. 
  

  

  Color 
  a 
  clear 
  cartilage 
  gray, 
  thickly 
  covered 
  on 
  the 
  dorsal 
  surface 
  

   with 
  small 
  spots 
  of 
  jet 
  black; 
  these 
  spots 
  are 
  circular 
  in 
  outline 
  and 
  

   are 
  thickest 
  along 
  the 
  midline 
  where 
  they 
  extend 
  the 
  entire 
  length 
  of 
  

   the 
  body. 
  

  

  Total 
  length, 
  2.05 
  mm. 
  Carapace, 
  1.1 
  mm. 
  long, 
  0,95 
  mm. 
  wide. 
  

   Genital 
  segment, 
  0.65 
  mm. 
  long 
  and 
  the 
  same 
  width. 
  Abdomen, 
  

   0.15 
  mm. 
  long. 
  Egg-strings, 
  0.8 
  mm. 
  long. 
  

  

  (atromaculatus, 
  ater, 
  black, 
  and 
  maculatus, 
  spotted.) 
  

  

  This 
  tiny 
  species 
  proved 
  to 
  be 
  very 
  sluggish 
  when 
  transferred 
  to 
  

   an 
  aquarium 
  and 
  did 
  not 
  swim 
  about 
  at 
  all, 
  simply 
  lying 
  on 
  its 
  back 
  

   and 
  moving 
  its 
  appendages 
  feebly. 
  Its 
  distinguishing 
  characters 
  are 
  

   the 
  black 
  spots 
  on 
  the 
  dorsal 
  surface, 
  the 
  large 
  circular 
  lunules, 
  the 
  

   spatulate 
  tips 
  of 
  the 
  first 
  maxillae, 
  the 
  long 
  and 
  club-shaped 
  rami 
  of 
  

   the 
  furca, 
  and 
  the 
  weak 
  and 
  slender 
  fourth 
  legs. 
  

  

  CALIGUS 
  AFURCATUS, 
  new 
  species. 
  

   Plate 
  30, 
  figs. 
  102-106; 
  plate 
  32, 
  figs. 
  136-138. 
  

  

  Host 
  and 
  record 
  of 
  specimens. 
  — 
  ^Three 
  females 
  with 
  egg-strings 
  were 
  

   found 
  fastened 
  to 
  the 
  sides 
  of 
  the 
  filaments, 
  m 
  the 
  spaces 
  between 
  

   adjacent 
  filaments, 
  on 
  the 
  gills 
  of 
  an 
  8-pound 
  green 
  parrot 
  fish, 
  Spari- 
  

   soma 
  viride, 
  in 
  company 
  with 
  the 
  following 
  species. 
  

  

  Type-specimen. 
  — 
  Cat. 
  No. 
  43518, 
  U.S.N.M. 
  Paratypes, 
  Cat. 
  No. 
  

   42259, 
  U.S.N.M. 
  

  

  Female. 
  — 
  General 
  body 
  form 
  short 
  and 
  stout; 
  carapace 
  ovate, 
  one- 
  

   eighth 
  longer 
  than 
  wide, 
  narrowed 
  anteriorly; 
  frontal 
  plates 
  narrow 
  

   and 
  not 
  prominent; 
  lunules 
  small, 
  widely 
  separated, 
  circular, 
  and 
  not 
  

   projecting; 
  eye 
  small; 
  lateral 
  areas 
  narrow, 
  lateral 
  lobes 
  bluntly 
  

   rounded 
  and 
  inclined 
  inward; 
  median 
  lobe 
  half 
  the 
  entire 
  width 
  and 
  

   projecting 
  for 
  half 
  its 
  length 
  behind 
  the 
  lateral 
  lobes; 
  posterior 
  sinuses 
  

   narrow 
  and 
  inclined 
  outward; 
  crossbar 
  of 
  the 
  H 
  grooves 
  convex 
  

  

  