﻿230 
  Prof. 
  Carl 
  Chun 
  on 
  the 
  

  

  female 
  group 
  to 
  every 
  four 
  to 
  six 
  male 
  groups. 
  In 
  the 
  last 
  

   groups 
  of 
  appendages 
  first 
  the 
  stomachal 
  sac 
  and 
  tentacles 
  

   and 
  finally 
  the 
  bract 
  become 
  rudimentary. 
  

  

  Epibulia 
  monoica 
  is 
  a 
  very 
  characteristic 
  Canarian 
  form, 
  in 
  

   which 
  I 
  was 
  able 
  to 
  trace 
  with 
  particular 
  exactitude 
  the 
  

   peculiar 
  retrogression 
  of 
  the 
  Eudoxia-gvoups. 
  Usually 
  in 
  the 
  

   older 
  examples 
  we 
  find 
  at 
  the 
  end 
  of 
  the 
  stem 
  from 
  four 
  to 
  

   six 
  gonocalyces, 
  to 
  which 
  the 
  rudiments 
  of 
  the 
  shrunken 
  

   -EWcm'a-constituents 
  adhere. 
  The 
  mature 
  testes 
  are 
  rose- 
  

   coloured, 
  and, 
  like 
  the 
  mature 
  ovaria, 
  occupy 
  nearly 
  the 
  

   whole 
  of 
  the 
  subumbrellar 
  space. 
  The 
  species 
  under 
  con- 
  

   sideration 
  has 
  in 
  common 
  with 
  Epibulia 
  aurantiaca 
  not 
  only 
  

   the 
  convolutions 
  of 
  the 
  vessels, 
  but 
  also 
  the 
  commissure 
  be- 
  

   tween 
  the 
  lateral 
  and 
  ventral 
  vascular 
  stems 
  in 
  the 
  superior 
  

   calyx. 
  It 
  is 
  distinguished 
  therefrom, 
  besides 
  the 
  above-men- 
  

   tioned 
  characters, 
  by 
  the 
  different 
  formation 
  of 
  the 
  so-called 
  

   closing 
  valves 
  on 
  the 
  margin 
  of 
  the 
  umbrella. 
  From 
  the 
  

   two 
  species 
  described 
  by 
  Sars*, 
  E. 
  truncata 
  and 
  E. 
  biloba, 
  as 
  

   also 
  from 
  E. 
  Sarsii, 
  Gegenbaur 
  f, 
  it 
  differs 
  by 
  the 
  small 
  size 
  

   of 
  the 
  fluid-receptacle 
  and 
  the 
  complicated 
  structure 
  of 
  the 
  

   umbrellar 
  margin. 
  

  

  The 
  polypites 
  are 
  very 
  slender, 
  with 
  an 
  elongated 
  cnida- 
  

   rium 
  and 
  a 
  light 
  brown 
  median 
  stomachal 
  section. 
  Epibulia 
  

   monoica 
  attains 
  a 
  length 
  of 
  28 
  millim. 
  ; 
  in 
  the 
  largest 
  speci- 
  

   men 
  the 
  inferior 
  calyx 
  was 
  twice 
  as 
  long 
  as 
  the 
  upper 
  one. 
  

   A 
  few 
  examples 
  occurred 
  in 
  January 
  and 
  March. 
  

  

  9. 
  Epibulia 
  aurantiaca, 
  var. 
  canariensis. 
  

  

  I 
  observed 
  a 
  species 
  nearly 
  allied 
  to 
  E. 
  aurantiaca, 
  and, 
  

   like 
  this, 
  dioecious, 
  twice 
  in 
  March. 
  It 
  showed 
  the 
  diver- 
  

   ticula 
  of 
  the 
  subumbrella 
  less 
  strongly 
  developed 
  on 
  the 
  

   inferior 
  calyx 
  and 
  presented 
  some 
  differences 
  in 
  the 
  develop- 
  

   ment 
  of 
  the 
  teeth 
  projecting 
  from 
  the 
  umbrellar 
  margin. 
  As, 
  

   however, 
  the 
  differences 
  are 
  probably 
  only 
  unimportant, 
  1 
  

   regard 
  the 
  Canarian 
  form 
  for 
  the 
  present 
  only 
  as 
  a 
  variety 
  of 
  

   E. 
  aurantiaca. 
  

  

  10. 
  Diphyes 
  subtilis, 
  Chun. 
  

  

  D. 
  subtilis 
  makes 
  the 
  transition 
  between 
  the 
  genera 
  Epi- 
  

   bulia 
  and 
  Diphyes. 
  It 
  has 
  no 
  hydrcecium 
  and, 
  like 
  the 
  true 
  

   Epibulice, 
  possesses 
  wing- 
  like 
  edges 
  on 
  the 
  inferior 
  calyx, 
  

   but 
  has 
  in 
  common 
  with 
  the 
  Diphyids 
  the 
  formation 
  of 
  sepa- 
  

  

  * 
  ' 
  Fauna 
  littoralis 
  Norvegiae,' 
  i. 
  (1846), 
  pp. 
  41-46, 
  pi. 
  7. 
  

  

  f 
  Nova 
  Acta 
  Ac. 
  Cscs. 
  Leop.-Car. 
  xxvii. 
  (1859) 
  p. 
  372, 
  pl.xxix. 
  tig. 
  30. 
  

  

  