﻿PYCNOGONIDA 
  FROM 
  JAPANESE 
  WATERS 
  — 
  HEDGPETH 
  265 
  

  

  Abdomen 
  longer 
  than 
  lateral 
  process, 
  slightly 
  curved, 
  tapering 
  in 
  

   distal 
  half, 
  directed 
  at 
  an 
  angle 
  of 
  45°. 
  

  

  Chelif 
  ore 
  : 
  Scape 
  heavy, 
  about 
  as 
  long 
  as 
  proboscis 
  ; 
  chela 
  longer 
  than 
  

   scape, 
  slender, 
  curved. 
  About 
  15 
  to 
  25 
  large 
  well-separated 
  teeth 
  on 
  

   immovable 
  claw 
  and 
  from 
  16 
  to 
  30 
  teeth 
  on 
  the 
  dactylus. 
  

  

  Palpus 
  slender, 
  straight, 
  with 
  fine 
  setae 
  on 
  the 
  terminal 
  joints. 
  In 
  

   some 
  specimens 
  the 
  fourth 
  joint 
  is 
  noticeably 
  shorter 
  than 
  the 
  fifth 
  ; 
  in 
  

   others 
  it 
  is 
  almost 
  as 
  long. 
  

  

  Third 
  leg: 
  First 
  and 
  third 
  coxae 
  subequal, 
  from 
  slightly 
  longer 
  

   than 
  their 
  diameter 
  to 
  almost 
  twice 
  that 
  length. 
  Second 
  coxa 
  about 
  

   as 
  long 
  as 
  first 
  and 
  third 
  together. 
  Femur 
  slightly 
  arched, 
  slightly 
  

   shorter 
  than 
  first 
  tibia. 
  Tibiae 
  straight, 
  sticklike, 
  subequal, 
  with 
  a 
  

   scattering 
  of 
  fine 
  setae. 
  Tarsus 
  and 
  propodus 
  subequal, 
  with 
  a 
  row 
  

   of 
  well-separated 
  fine 
  spines 
  along 
  the 
  ventral 
  surface. 
  Terminal 
  

   claw 
  almost 
  straight, 
  as 
  long 
  as 
  propodus. 
  No 
  auxiliary 
  claws. 
  

  

  Oviger: 
  Fourth 
  joint 
  slightly 
  curved; 
  fifth 
  joint 
  almost 
  straight, 
  

   expanded 
  distally 
  to 
  about 
  twice 
  the 
  median 
  diameter. 
  Compound 
  

   spines 
  large, 
  with 
  three 
  or 
  four 
  pairs 
  of 
  coarse 
  denticulations. 
  Ter- 
  

   minal 
  claw 
  almost 
  as 
  long 
  as 
  terminal 
  joint, 
  with 
  6 
  to 
  12 
  widely 
  sepa- 
  

   rated 
  spines. 
  There 
  are 
  usually 
  six 
  or 
  seven 
  compound 
  spines 
  on 
  each 
  

   joint. 
  Formula 
  : 
  7 
  : 
  7 
  : 
  6 
  : 
  7 
  : 
  : 
  7. 
  

  

  Measurements 
  (holotype) 
  as 
  follows: 
  

  

  Mm. 
  

  

  Proboscis 
  2. 
  

  

  Trunk 
  7.5 
  

  

  Second 
  lateral 
  process, 
  width 
  3. 
  5 
  

  

  Abdomen 
  1. 
  

  

  Scape 
  2.1 
  

  

  Chela 
  2.5 
  

  

  Palpus 
  4. 
  5 
  

  

  Third 
  leg 
  : 
  Mm. 
  

  

  First 
  coxa 
  0. 
  75 
  

  

  Second 
  coxa 
  2. 
  

  

  Third 
  coxa 
  1. 
  

  

  Femur 
  5. 
  1 
  

  

  First 
  tibia 
  6.0 
  

  

  Second 
  tibia 
  9.0 
  

  

  Tarsus 
  1. 
  8 
  

  

  Propodus 
  1.9 
  

  

  Terminal 
  claw 
  2. 
  1 
  

  

  Remarks. 
  — 
  This 
  species 
  is 
  close 
  to 
  Nym/plion 
  longicoxa 
  Hoek, 
  from 
  

   the 
  South 
  Pacific 
  near 
  Auckland, 
  but 
  it 
  differs 
  in 
  the 
  following 
  re- 
  

   spects: 
  The 
  terminal 
  claw 
  is 
  much 
  longer, 
  and 
  the 
  male 
  oviger 
  is 
  

   straighter 
  and 
  lacks 
  the 
  peculiar 
  processes 
  on 
  the 
  dorsum 
  described 
  

   by 
  Hoek. 
  In 
  many 
  specimens 
  the 
  fourth 
  joint 
  of 
  the 
  palpus 
  is 
  

   shorter, 
  but 
  the 
  variable 
  length 
  of 
  this 
  joint 
  suggests 
  a 
  close 
  relation- 
  

   ship 
  with 
  Hoek's 
  species. 
  There 
  is, 
  however, 
  no 
  variation 
  in 
  the 
  

   length 
  of 
  the 
  terminal 
  claw, 
  and 
  the 
  propodus 
  is 
  not 
  conspicuously 
  

   longer 
  than 
  the 
  tarsus 
  as 
  in 
  N. 
  longicoxa, 
  nor 
  does 
  N. 
  aTbatrossi 
  have 
  

   the 
  very 
  long 
  second 
  coxae 
  of 
  that 
  species. 
  It 
  is 
  readily 
  distinguished 
  

   from 
  N. 
  uniunguiculatum 
  by 
  the 
  shorter 
  fourth 
  joint 
  of 
  the 
  palpus, 
  

   the 
  larger 
  teeth 
  in 
  the 
  chelae, 
  the 
  coarser 
  denticulations 
  of 
  the 
  spines 
  

   of 
  the 
  oviger, 
  and 
  the 
  much 
  longer 
  terminal 
  claw 
  of 
  the 
  legs. 
  This 
  

  

  793375 
  — 
  49 
  3 
  

  

  