﻿270 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol. 
  44. 
  

  

  Male. 
  — 
  Shell 
  subovate, 
  greatest 
  height 
  posterior 
  to 
  the 
  center, 
  

   ventral 
  and 
  dorsal 
  margins 
  evenly 
  rounded; 
  posterior 
  end 
  formed 
  

   by 
  the 
  continued 
  even 
  sweep 
  of 
  the 
  dorsal 
  margin, 
  but 
  with 
  the 
  

   lower 
  portion 
  protruding 
  somewhat 
  as 
  in 
  C. 
  mediterranea. 
  Antennal 
  

   sinus 
  narrow 
  and 
  not 
  very 
  deep, 
  with 
  parallel 
  sides; 
  rostrate 
  process 
  

   wide, 
  well 
  arched 
  anteriorly, 
  acute 
  at 
  the 
  point 
  and 
  directed 
  down- 
  

   ward 
  and 
  slightly 
  backward. 
  Eye 
  large 
  and 
  at 
  about 
  the 
  center 
  

   of 
  the 
  shell 
  dorso-ventrally 
  but 
  considerably 
  in 
  frontof 
  the 
  antero- 
  

   posterior 
  center. 
  Length 
  of 
  shell, 
  1.8 
  mm.; 
  height, 
  1.15 
  mm. 
  

  

  Antennules 
  rather 
  stout; 
  terminal 
  joint 
  with 
  three 
  long 
  setse 
  of 
  equal 
  

   length; 
  sensory 
  appendage 
  on 
  the 
  fifth 
  joint 
  long, 
  distinctly 
  ringed 
  

   and 
  divided 
  at 
  the 
  tip, 
  its 
  secondary 
  filaments 
  short 
  and 
  flattened. 
  

   Antennae 
  of 
  the 
  usual 
  form, 
  swimming 
  branch 
  bearing 
  nine 
  setae, 
  the 
  

   basal 
  one 
  much 
  shorter 
  than 
  the 
  others; 
  appendicular 
  branch 
  with 
  a 
  

   very 
  short 
  basal 
  seta 
  and 
  a 
  long 
  and 
  stout 
  terminal 
  one, 
  carrying 
  a 
  

   short 
  secondary 
  seta 
  on 
  its 
  inner 
  margin. 
  Hirsute 
  masticatory 
  lobe 
  

   of 
  the 
  mandibles 
  large 
  and 
  prominent; 
  basal 
  joint 
  of 
  the 
  palp 
  consid- 
  

   erably 
  swollen; 
  subterminal 
  joint 
  about 
  half 
  the 
  entire 
  length, 
  ter- 
  

   minal 
  claws 
  stout 
  and 
  of 
  the 
  same 
  size. 
  

  

  First 
  maxilla 
  broad 
  and 
  stout, 
  with 
  a 
  long 
  and 
  slender 
  palp, 
  thickly 
  

   armed 
  with 
  setae 
  at 
  its 
  tip; 
  second 
  maxilla 
  rather 
  slender 
  with 
  broad 
  

   and 
  flattened 
  setae; 
  vibratory 
  lamina 
  narrow, 
  its 
  setae 
  increasing 
  in 
  

   length 
  from 
  the 
  tip 
  toward 
  the 
  base; 
  third 
  maxilla 
  wide 
  and 
  stout, 
  

   vibratory 
  lamina 
  broadly 
  triangular 
  and 
  armed 
  mth 
  two 
  long 
  setae 
  

   at 
  the 
  outer 
  corner 
  and 
  six 
  shorter 
  ones 
  along 
  the 
  basal 
  portion 
  of 
  the 
  

   anterior 
  margin, 
  with 
  a 
  considerable 
  space 
  between 
  the 
  two 
  devoid 
  

   of 
  armature. 
  Vermiform 
  leg 
  armed 
  with 
  10 
  to 
  12 
  very 
  slender 
  cilia 
  

   along 
  either 
  margin 
  and 
  one 
  or 
  two 
  at 
  the 
  end. 
  Caudal 
  lamina 
  with 
  

   14 
  spines, 
  gradually 
  increasing 
  in 
  length 
  from 
  the 
  base 
  towartl 
  the 
  

   tip, 
  the 
  last 
  three 
  much 
  shorter 
  than 
  the 
  others 
  and 
  of 
  nearly 
  the 
  same 
  

   length. 
  

  

  Female 
  unknown. 
  

  

  LIST 
  OF 
  HOSTS, 
  WITH 
  PARASITES 
  FOUND 
  ON 
  EACH. 
  

  

  SPHYRNA 
  ZYG^ENA. 
  Hammerhead 
  shark. 
  

  

  Erga-sUus 
  mijctarothes 
  Wilson, 
  Ihong 
  in 
  the 
  nasal 
  tubes. 
  

  

  Txniacanthus 
  flagellars 
  Wilson, 
  from 
  the 
  gill 
  cavities 
  close 
  to 
  the 
  edge 
  of 
  the 
  gill 
  filaments. 
  

  

  Lepeophtheirus 
  loTigispinosus 
  Wilson, 
  from 
  the 
  inside 
  of 
  the 
  gill 
  cavity. 
  

  

  Nemem 
  versicolor 
  Wilson, 
  attached 
  to 
  the 
  gill 
  filaments. 
  

  

  Cypridina 
  parasitica 
  Wilson, 
  the 
  ostracod, 
  between 
  the 
  gill 
  filaments 
  at 
  thtir 
  base. 
  

  

  DASYATIS 
  HASTATA. 
  Sting 
  ray. 
  

  

  Brachiclla 
  concava 
  Wilson, 
  from 
  the 
  gill 
  arches. 
  

  

  HEMIRAMPHUS 
  BRASILIENSIS. 
  Balao. 
  

  

  Lernxolophus 
  hemiramphi 
  Kr0yer, 
  from 
  the 
  mouth 
  opening. 
  

  

  EXOCCETUS 
  VOLITANS. 
  Flying 
  fish. 
  

  

  PenneHa 
  «:ocarti(Holten), 
  with 
  its 
  head 
  and 
  anterior 
  body 
  buried 
  in 
  the 
  flesh 
  along 
  the 
  side 
  of 
  thefishs' 
  

   body. 
  

  

  