﻿260 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  96 
  

  

  Genus 
  ACANTHOHAMINGIA 
  Ikeda, 
  emended 
  

  

  Acanthohamingia 
  Ikeda, 
  1910, 
  p. 
  136. 
  (Type, 
  A. 
  shiplei 
  Ikeda.) 
  

  

  Diagnosis. 
  — 
  Differing 
  from 
  Hamingia 
  in 
  having 
  a 
  well-marked 
  

   genital 
  slit 
  extending 
  forward 
  toward 
  mouth 
  from 
  the 
  one 
  or 
  two 
  

   nephridiopores, 
  this 
  containing, 
  in 
  two 
  species, 
  8 
  or 
  10 
  very 
  small 
  

   setae 
  imbedded 
  in 
  the 
  skin; 
  anal 
  vesicles 
  numerous, 
  at 
  least 
  not 
  in 
  

   two 
  symmetrical 
  clumps 
  which 
  arise 
  from 
  a 
  very 
  short 
  common 
  duct; 
  

   body 
  wall 
  thin; 
  proboscis 
  (when 
  known) 
  similar 
  to 
  that 
  of 
  Thalassema; 
  

   males 
  with 
  or 
  without 
  ventral 
  setae. 
  

  

  Remarks. 
  — 
  The 
  new 
  species 
  described 
  below 
  has 
  necessitated 
  an 
  

   emendation 
  of 
  the 
  original 
  diagnosis 
  since 
  there 
  are 
  no 
  minute 
  setao 
  

   in 
  the 
  genital 
  groove. 
  This 
  groove, 
  which 
  extends 
  forward 
  from 
  the 
  

   nephridiopore, 
  or 
  pores, 
  occurs 
  in 
  the 
  three 
  known 
  species 
  ^^ 
  and 
  is 
  not 
  

   present 
  in 
  any 
  other 
  genus. 
  The 
  general 
  habit 
  of 
  the 
  three 
  species 
  is 
  

   much 
  the 
  same, 
  as 
  they 
  are 
  all 
  of 
  delicate 
  build. 
  The 
  body 
  wall 
  is 
  

   thin, 
  translucent 
  when 
  expanded, 
  and 
  skin 
  papillae 
  are 
  poorly 
  devel- 
  

   oped. 
  The 
  anal 
  trees 
  exhibit 
  differences 
  in 
  the 
  three 
  species, 
  being 
  

   most 
  alike 
  in 
  A. 
  ijimai 
  and 
  A. 
  paradola. 
  These 
  are 
  numerous, 
  inde- 
  

   pendent, 
  or 
  semi-independent 
  branched 
  tubules, 
  and 
  differ 
  from 
  the 
  

   condition 
  in 
  any 
  other 
  genus 
  except 
  Nellobia. 
  But 
  in 
  Nellobia 
  eusoma, 
  

   which 
  lacks 
  any 
  trace 
  of 
  a 
  genital 
  groove 
  and 
  is 
  one 
  of 
  the 
  most 
  heavily 
  

   built 
  of 
  all 
  bonelliids, 
  the 
  anal 
  trees 
  spring 
  from 
  a 
  bladderlike 
  struc- 
  

   ture 
  applied 
  to 
  each 
  side 
  of 
  the 
  very 
  muscular 
  cloaca. 
  The 
  rudi- 
  

   mentary 
  bladder 
  figured 
  for 
  A. 
  paradola 
  (left 
  side) 
  may 
  well 
  indicate 
  

   the 
  last 
  trace 
  of 
  a 
  similar 
  structure. 
  

  

  In 
  A. 
  shiplei 
  and 
  A. 
  ijimai 
  the 
  male 
  is 
  long 
  and 
  slender 
  and 
  Iscks 
  

   setae, 
  whereas 
  in 
  A. 
  paradola 
  the 
  male 
  is 
  lanceolate 
  and 
  planarian- 
  

   like 
  and 
  is 
  provided 
  with 
  two 
  curved 
  setae. 
  

  

  ACANTHOHAMINGIA 
  PARADOLA, 
  new 
  species 
  

  

  Plates 
  31, 
  32 
  

  

  Diagnosis. 
  — 
  Dijffering 
  from 
  A. 
  shiplei 
  and 
  A. 
  ijimai 
  in 
  the 
  absence 
  

   of 
  minute 
  setae 
  from 
  the 
  genital 
  groove 
  of 
  female 
  and 
  in 
  the 
  presence 
  

   of 
  a 
  pair 
  of 
  ventral 
  curved 
  setae 
  in 
  the 
  male; 
  nephridia 
  2 
  instead 
  of 
  1; 
  

   anal 
  trees 
  numerous, 
  slender, 
  sparsely 
  branched, 
  arising 
  for 
  the 
  most 
  

   part 
  independently 
  from 
  the 
  very 
  thin 
  wall 
  of 
  the 
  cloaca. 
  Length 
  of 
  

   paratype 
  90 
  mm. 
  (pi, 
  31, 
  fig. 
  1). 
  Color, 
  pale 
  flesh 
  when 
  seen 
  on 
  a 
  

   white 
  background. 
  

  

  Description. 
  — 
  The 
  general 
  habit 
  is 
  much 
  like 
  that 
  of 
  A. 
  ijimai 
  but 
  

   proboscis 
  is 
  lacking. 
  The 
  body 
  wall 
  is 
  very 
  thin 
  and 
  translucent, 
  

   this 
  thinness 
  being 
  accentuated 
  by 
  inflation. 
  Along 
  the 
  midventral 
  

   line 
  the 
  extremely 
  slender 
  nerve 
  cord 
  can 
  be 
  easily 
  seen. 
  The 
  skin 
  

  

  I 
  A. 
  shiplei 
  Ikeda 
  1910, 
  p. 
  136, 
  pi. 
  10; 
  Hamingia 
  ijimai 
  Ikeda, 
  1908b, 
  p. 
  62, 
  pi. 
  1. 
  

  

  