﻿10 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol.44. 
  

  

  than 
  in 
  the 
  smaller 
  specimens 
  usually 
  described, 
  for 
  each 
  tentacle 
  

   forks 
  seven 
  or 
  eight 
  times. 
  

  

  Color. 
  — 
  Ocelli 
  are 
  dark 
  brown, 
  almost 
  black; 
  the 
  manubrium 
  pale 
  

   reddish 
  brown. 
  

  

  Genus 
  RATHKEA 
  Brandt, 
  1837 
  (Hartlaub). 
  

  

  It 
  seems 
  that 
  at 
  last 
  the 
  generic 
  name 
  for 
  Bougainvilleidae, 
  with 
  

   eight 
  groups 
  of 
  marginal 
  tentacles 
  and 
  with 
  the 
  labial 
  tentacles 
  

   represented 
  by 
  nematocyst 
  swellings 
  at 
  the 
  corners 
  of 
  the 
  lip, 
  is 
  

   settled. 
  The 
  stumbling 
  block 
  has 
  long 
  been 
  Raihkea 
  hlumenhachii 
  

   (Rathke) 
  Brandt 
  from 
  the 
  Black 
  Sea, 
  a 
  form 
  so 
  poorly 
  figured 
  that 
  

   it 
  was 
  impossible 
  to 
  determine 
  the 
  type 
  of 
  oral 
  appendages; 
  but 
  

   Hartlaub 
  (1911) 
  has 
  recently 
  studied 
  series 
  from 
  the 
  Black 
  Sea 
  which 
  

   prove 
  indistinguishable 
  from 
  the 
  common 
  Lizzia 
  octcpunctata 
  of 
  the 
  

   North 
  Atlantic, 
  and 
  likewise 
  specimens 
  of 
  that 
  species 
  from 
  the 
  

   Mediterranean 
  (Trieste, 
  Cette). 
  There 
  is, 
  then, 
  no 
  further 
  question 
  

   that 
  hlumenhachii 
  and 
  octopunctata 
  are 
  identical, 
  and 
  Lizzia 
  must 
  

   give 
  way 
  to 
  Ratlikea. 
  

  

  The 
  common 
  Mediterranean 
  species 
  fascicularis 
  thus 
  loses 
  the 
  

   generic 
  name 
  which 
  Maas 
  (1905) 
  and 
  I 
  formerly 
  applied 
  to 
  it, 
  and 
  

   Browne 
  (1910) 
  has 
  revived 
  KoUilceria 
  for 
  it 
  and 
  similar 
  species. 
  

   Mayer 
  (1910) 
  uses 
  Ratlikea 
  m 
  a 
  broad 
  sense 
  to 
  include 
  all 
  Bougain- 
  

   villeidae 
  with 
  eight 
  groups 
  of 
  marginal 
  tentacles. 
  But 
  I 
  agree 
  with 
  

   Maas 
  and 
  with 
  Hartlaub 
  that 
  the 
  structure 
  of 
  the 
  labial 
  appendages 
  

   is 
  sufficiently 
  important 
  to 
  afford 
  a 
  generic 
  character 
  of 
  phylogenetic 
  

   value, 
  and 
  it 
  warrants 
  at 
  least 
  two 
  and 
  probably 
  three 
  genera, 
  Rathkea 
  

   with 
  simple 
  nematocyst 
  knobs, 
  Lizzia 
  with 
  unbranched 
  labial 
  ten- 
  

   tacles 
  and 
  KoUilceria 
  with 
  branched 
  labial 
  tentacles. 
  The 
  species 
  

   included 
  m 
  Rathkea 
  by 
  Mayer 
  are 
  hlumenhachii 
  Rathke, 
  /ormos-issma 
  

   Browne, 
  octopunctata 
  Sa,rs, 
  fasciculata 
  Peron 
  and 
  Lesueur, 
  octonemalis 
  

   Maas, 
  elegans 
  Mayer, 
  and 
  hlondina 
  Forbes. 
  According 
  to 
  the 
  above 
  

   definition, 
  these 
  species 
  should 
  be 
  distributed 
  as 
  follows: 
  hlumen- 
  

   hachii 
  { 
  = 
  octopunctata) 
  to 
  RathJcea; 
  fasciculata, 
  octonemalis, 
  and 
  elegans 
  

   to 
  KolliJceria; 
  hlondina 
  to 
  Lizzia; 
  void 
  formosissima 
  also 
  probably 
  to 
  

   Lizzia. 
  

  

  Hartlaul) 
  (1911) 
  makes 
  a 
  different 
  division, 
  referring 
  to 
  BougainviUea 
  

   species 
  with 
  branched 
  oral 
  tentacles, 
  and 
  smooth, 
  not 
  folded, 
  gonads 
  

   and 
  gastric 
  walls, 
  irrespective 
  of 
  the 
  number 
  of 
  bundles 
  of 
  marginal 
  

   tentacles; 
  that 
  is, 
  octonemalis 
  and 
  elegans. 
  But 
  though 
  Bougainvil- 
  

   leas 
  do 
  var}^ 
  more 
  or 
  less 
  in 
  number 
  of 
  bundles, 
  still 
  the 
  octoradial 
  

   condition 
  of 
  Kollikeria 
  is 
  precise; 
  it 
  does 
  not 
  intergrade 
  in 
  any 
  true 
  

   sense 
  with 
  the 
  quadriradiality 
  of 
  BougainviUea. 
  

  

  Mayer 
  (1910, 
  p. 
  179) 
  recognizes 
  a 
  variety 
  of 
  hlumenhachii, 
  grata, 
  for 
  

   specimens 
  wdth 
  a 
  long 
  peduncle; 
  but 
  I 
  doubt 
  whether 
  the 
  difference 
  

  

  