﻿246 
  PROCEEDINGS 
  OF 
  TEE 
  NATIONAL 
  MUSEUM. 
  vol.44. 
  

  

  it 
  is 
  just 
  the 
  opposite 
  in 
  every 
  particular 
  of 
  what 
  would 
  be 
  expected 
  

   on 
  sucli 
  a 
  long 
  and 
  powerful 
  basal 
  joint. 
  Mouth 
  tube 
  elliptical 
  in 
  

   outline 
  with 
  a 
  squarely 
  truncated 
  tip, 
  one-lialf 
  longer 
  than 
  wide. 
  

  

  Maxillae 
  distinctly 
  showing 
  as 
  papillae 
  on 
  eitlier 
  side 
  of 
  the 
  mouth 
  

   tube, 
  each 
  tipped 
  with 
  three 
  setae 
  verj'^ 
  similar 
  to 
  those 
  of 
  the 
  Erga- 
  

   silidae. 
  Swimming 
  legs 
  witli 
  long 
  and 
  narrow 
  basal 
  joints, 
  the 
  prox- 
  

   imal 
  joint 
  of 
  the 
  exopod 
  longer 
  than 
  the 
  one-jointed 
  endopod. 
  Third 
  

   legs 
  present 
  as 
  minute 
  papillae 
  on 
  the 
  lateral 
  margins, 
  each 
  tii)ped 
  with 
  

   two 
  spines; 
  fourth 
  legs 
  indicated 
  by 
  a 
  paii* 
  of 
  single 
  spines, 
  also 
  on 
  

   the 
  lateral 
  margins. 
  

  

  Color 
  a 
  uniform 
  translucent 
  yellowish-white, 
  the 
  eggs 
  in 
  the 
  ovi- 
  

   ducts 
  a 
  light 
  brown, 
  those 
  in 
  the 
  external 
  sacks 
  a 
  dark 
  seal-brown. 
  

  

  Total 
  length, 
  0.85 
  mm. 
  Carapace, 
  0.28 
  mm. 
  long 
  and 
  wide. 
  

   Fused 
  thorax, 
  0.55 
  mm. 
  long, 
  0.37 
  mm, 
  wide. 
  Egg-strings, 
  0.45 
  mm. 
  

   long, 
  0.12 
  mm. 
  wide 
  at 
  the 
  distal 
  end. 
  

  

  (insolitus, 
  unusual, 
  alluding 
  to 
  the 
  second 
  antennae 
  and 
  the 
  rudi- 
  

   mentary 
  third 
  and 
  fourth 
  legs.) 
  

  

  Although 
  found 
  upon 
  the 
  same 
  host 
  as 
  the 
  preceding 
  species, 
  the 
  

   present 
  form 
  is 
  readily 
  distinguished 
  by 
  the 
  length 
  of 
  the 
  second 
  

   antennae 
  and 
  the 
  peculiar 
  shape 
  of 
  their 
  terminal 
  claw 
  and 
  by 
  the 
  

   presence 
  of 
  the 
  rudiments 
  of 
  the 
  third 
  and 
  fourth 
  pairs 
  of 
  legs 
  in 
  the 
  

   sinuses 
  on 
  the 
  lateral 
  margins. 
  In 
  this 
  last 
  respect 
  it 
  resembles 
  

   Hatschekia 
  {Clavella) 
  labracis 
  Van 
  Beneden. 
  

  

  HATSCHEKIA 
  LINEARIS, 
  new 
  species. 
  

  

  Plate 
  44, 
  figs. 
  240-246. 
  

  

  Host 
  and 
  record 
  ofsj)ecimens. 
  — 
  Ten 
  females 
  were 
  obtained 
  from 
  the 
  

   gills 
  of 
  the 
  red-mouthed 
  grunt, 
  Bathystoma 
  rimator, 
  July 
  14, 
  1910. 
  

   They 
  were 
  attached 
  with 
  their 
  long 
  axis 
  parallel 
  to 
  the 
  filament 
  and 
  

   on 
  its 
  outer 
  surface. 
  

  

  Type-specimen. 
  — 
  Cat. 
  No. 
  43551, 
  U.S.N.M. 
  Paratypes, 
  Cat. 
  No. 
  

   42293, 
  U.S.N.M. 
  

  

  Female. 
  — 
  General 
  body 
  form 
  linear, 
  seven 
  times 
  as 
  long 
  as 
  wide, 
  and 
  

   made 
  up 
  of 
  four 
  distinctly 
  separated 
  parts: 
  the 
  head; 
  the 
  first 
  and 
  

   second 
  thorax 
  segments 
  partially 
  fused; 
  the 
  third, 
  fourth, 
  and 
  fifth 
  

   segments 
  completely 
  fused 
  ; 
  and 
  the 
  sixth 
  segment 
  and 
  abdomen 
  also 
  

   completely 
  fused. 
  Carapace 
  very 
  small 
  and 
  circular, 
  only 
  one-ninth 
  

   of 
  the 
  entire 
  length, 
  and 
  a 
  little 
  narrower 
  than 
  the 
  posterior 
  body, 
  

   with 
  regular 
  outlines; 
  first 
  and 
  second 
  antennae 
  entirely 
  concealed 
  in 
  

   dorsal 
  view. 
  First 
  and 
  second 
  thorax 
  segments 
  longer 
  than 
  the 
  head, 
  

   a 
  little 
  narrower 
  anteriorly, 
  but 
  much 
  widened 
  posteriorly 
  through 
  

   the 
  bases 
  of 
  the 
  second 
  legs. 
  Fused 
  third, 
  fourth, 
  and 
  fifth 
  segments 
  

   linear, 
  five 
  times 
  as 
  long 
  as 
  wide 
  and 
  tapering 
  slightly 
  posteriorly, 
  

   with 
  nearly 
  straight 
  sides; 
  third 
  segment 
  contracted 
  into 
  a 
  narrow 
  

   neck 
  anteriorly 
  where 
  it 
  joins 
  the 
  second 
  segment, 
  leavmg 
  the 
  second 
  

  

  