﻿172 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  103 
  

  

  Polycelis 
  nigra 
  (O.F.MulleT), 
  Europe 
  P. 
  polyopis 
  Zabusova 
  (1936), 
  Kam- 
  

  

  P. 
  receptaculosa 
  (Livanov 
  and 
  Zabusova, 
  chatka 
  

  

  1940), 
  Teletskoe 
  Lake 
  in 
  the 
  Altai 
  P. 
  karafto 
  Ijima 
  and 
  Kaburaki 
  (1916), 
  

   Mountains 
  Sakhalin 
  

  

  P. 
  eburnea 
  (Muth, 
  1912), 
  Aral 
  Sea 
  P. 
  sopporo 
  (Ijima 
  and 
  Kaburaki, 
  1916), 
  

   region 
  Japan 
  

  

  P. 
  ttfeeftca 
  Hyman 
  (1934), 
  Tibet 
  P. 
  coronata 
  (Girard, 
  1894), 
  Wyoming 
  

  

  P. 
  koslowi 
  (Zabusov, 
  1911), 
  Tibet 
  and 
  South 
  Dakota 
  

  

  P. 
  elongata 
  (Sabussowa, 
  1929), 
  Kam- 
  

   chatka 
  

  

  Subgenus 
  Seidlia 
  Zabusov 
  (1911, 
  suppl., 
  p. 
  7), 
  distinguished 
  by 
  an 
  

   extraordinarily 
  thick 
  muscle 
  zone 
  surrounding 
  the 
  male 
  atrium. 
  

   Zabusov's 
  (1916, 
  p. 
  273) 
  genus 
  Rjabuschinskya 
  likewise 
  belongs 
  here. 
  

   Species 
  of 
  the 
  subgenus: 
  

  

  Polycelis 
  sabussowi 
  (Seidl, 
  1911), 
  in- 
  P. 
  schmidti 
  (Zabusov, 
  1916), 
  including 
  

   eluding 
  Seidl's 
  species 
  Sorocelis 
  P. 
  ijimai 
  Kaburaki 
  (1922), 
  Kam- 
  

  

  sabussowi, 
  S. 
  lactea, 
  S. 
  stummeri 
  chatka, 
  Kurile 
  Islands, 
  and 
  Japan 
  

  

  (cf. 
  Kenk, 
  1936), 
  Turkestan 
  P. 
  auncu/a<a 
  Ijima 
  and 
  Kaburaki 
  (1916), 
  

  

  P. 
  relicta 
  (Sabussowa, 
  1929), 
  Kamchatka 
  Japan 
  

  

  P. 
  eurantron 
  (Zabusova, 
  1936), 
  Kam- 
  

   chatka 
  

  

  The 
  third 
  subgenus, 
  Ijimia 
  Bergendal 
  (1890, 
  p. 
  326), 
  is 
  charac- 
  

   terized 
  by 
  possessing 
  solid 
  adenodactyls 
  : 
  

  

  Polycelis 
  felina 
  (Dalyell), 
  including 
  P. 
  linkoi 
  Zabusov 
  (1901), 
  Onega 
  Lake 
  

   P. 
  cornuta 
  Johnson, 
  Europe 
  and 
  in 
  European 
  Russia 
  

  

  North 
  Africa 
  P. 
  oculi-marginata 
  (Palombi, 
  1931), 
  New 
  

  

  P. 
  tenuis 
  Ijima, 
  Europe 
  and 
  western 
  Guinea 
  (see 
  Beauchamp, 
  1947) 
  

  

  Asia 
  

  

  Two 
  species 
  of 
  the 
  genus 
  Polycelis 
  are 
  too 
  mcompletely 
  known 
  to 
  

   permit 
  their 
  assignment 
  to 
  either 
  the 
  subgenus 
  Polycelis 
  or 
  Seidlia: 
  

   P. 
  eudendrocoeloides 
  (Sabussowa, 
  1929) 
  from 
  the 
  Kamchatka 
  Penin- 
  

   sula 
  and 
  P. 
  tibetica 
  (Zabusov, 
  1911, 
  p. 
  349) 
  from 
  Tibet 
  (P. 
  tibetica 
  

   Hyman, 
  1934, 
  will 
  have 
  to 
  be 
  renamed 
  if 
  it 
  should 
  prove 
  to 
  be 
  different 
  

   from 
  Zabusov's 
  species) 
  . 
  

  

  Polycelis 
  borealis 
  is 
  clearly 
  a 
  member 
  of 
  the 
  subgenus 
  Polycelis. 
  

   It 
  differs 
  from 
  P. 
  nigra 
  in 
  having 
  weU-developed 
  auricles; 
  from 
  P. 
  

   elongata, 
  P. 
  polyopis, 
  and 
  P. 
  sapporo, 
  in 
  the 
  arrangement 
  of 
  the 
  eyes; 
  

   and 
  from 
  P. 
  coronata 
  and 
  P. 
  receptaculosa 
  in 
  the 
  structure 
  of 
  the 
  male 
  

   copulatory 
  organ. 
  The 
  reproductive 
  system 
  of 
  P. 
  karafto 
  has 
  not 
  been 
  

   described 
  adequately 
  and 
  thus 
  does 
  not 
  permit 
  a 
  comparison 
  with 
  

   that 
  of 
  the 
  Alaskan 
  species. 
  The 
  remaining 
  species 
  of 
  the 
  subgenus, 
  

   P. 
  eburnea, 
  P. 
  koslowi, 
  and 
  P. 
  tibetica 
  Hyman, 
  two 
  of 
  which 
  are 
  known 
  

   only 
  from 
  the 
  study 
  of 
  preserved 
  specimens, 
  agree 
  with 
  P. 
  borealis 
  

   in 
  being 
  pigmented 
  forms 
  with 
  prominent 
  auricles 
  and 
  in 
  having 
  

   a 
  similar 
  anatomy 
  of 
  the 
  copulatory 
  organs. 
  The 
  four 
  species 
  are 
  

  

  