﻿224 
  Prof. 
  Carl 
  Chun 
  on 
  the 
  

  

  Order 
  I. 
  CALYCOPHORIM}, 
  Leuck. 
  

  

  As 
  is 
  well 
  known, 
  a 
  part 
  of 
  the 
  Calycophoridae 
  is 
  remark- 
  

   able 
  for 
  the 
  faculty 
  of 
  producing 
  Eudoxiae. 
  Hackel 
  is 
  of 
  

   opinion 
  that 
  the 
  two 
  generations, 
  the 
  monogastric 
  (the 
  Eu- 
  

   doxiae) 
  and 
  the 
  polygastric, 
  must, 
  upon 
  practical 
  grounds, 
  be 
  

   classified 
  in 
  the 
  system 
  separately 
  and 
  side 
  by 
  side 
  in 
  the 
  same 
  

   way 
  as 
  the 
  Hydromedusae 
  and 
  their 
  polyp-nurses. 
  I 
  cannot 
  

   agree 
  with 
  him 
  in 
  this. 
  A 
  system 
  of 
  Medusae 
  founded 
  solely 
  

   upon 
  the 
  sexual 
  animals 
  is 
  so 
  far 
  justified 
  that 
  a 
  great 
  part 
  of 
  

   the 
  Medusae 
  are 
  developed 
  directly 
  without 
  any 
  alternation 
  of 
  

   generations. 
  However, 
  of 
  late 
  noticeable 
  attempts 
  have 
  been 
  

   made 
  to 
  establish 
  a 
  unitary 
  system 
  of 
  the 
  whole 
  of 
  the 
  Hydro- 
  

   medusae, 
  taking 
  into 
  account 
  at 
  the 
  same 
  time 
  the 
  Polypes 
  

   and 
  the 
  Medusae 
  which 
  remain 
  sessile 
  as 
  gonophores. 
  Be- 
  

   sides 
  that 
  the 
  process 
  of 
  Eudoxia-£oxm&t\oxi 
  is 
  not 
  to 
  be 
  

   paralleled 
  unconditionally 
  with 
  the 
  budding 
  of 
  the 
  Medusae 
  

   (even 
  though, 
  like 
  Hackel, 
  P. 
  E. 
  Miiller, 
  and 
  Metschnikoff, 
  

   we 
  were 
  to 
  refer 
  a 
  part 
  of 
  the 
  Eudoxian 
  colony 
  to 
  dislocated 
  

   organs 
  of 
  a 
  Medusa), 
  there 
  is 
  no 
  Eudoxia 
  which 
  is 
  directly 
  

   developed 
  in 
  such 
  a 
  manner 
  that 
  a 
  Eudoxia 
  is 
  produced 
  

   directly 
  from 
  the 
  ciliated 
  embryo. 
  We 
  may 
  recognize 
  all 
  

   so-called 
  monogastric 
  colonies, 
  after 
  the 
  discovery 
  of 
  Sars, 
  

   Leuckart, 
  Vogt, 
  and 
  Gegenbaur, 
  as 
  descendants 
  of 
  polygastric 
  

   Siphonophora. 
  The 
  attempt, 
  to 
  establish 
  a 
  peculiar 
  system 
  of 
  

   Eudoxiae 
  leads 
  to 
  the 
  citation 
  of 
  the 
  families 
  of 
  the 
  latter 
  as 
  cate- 
  

   goriesequivalent 
  to 
  the 
  farailiesof 
  the 
  parent-colonies. 
  Funda- 
  

   mentally, 
  in 
  Hackel's 
  system 
  three 
  systems 
  of 
  Calycophoridae 
  

   run 
  parallel 
  to 
  each 
  other, 
  one 
  of 
  them 
  founded 
  upon 
  the 
  

   liberated 
  P^udoxiae, 
  the 
  second 
  upon 
  the 
  nectocalyces 
  of 
  the 
  

   parent-colonies 
  belonging 
  to 
  them, 
  and 
  the 
  third 
  upon 
  those 
  

   Calycophoridae 
  in 
  which 
  the 
  Eudoxiae 
  remain 
  sessile. 
  Such 
  

   an 
  attempt 
  leads 
  to 
  the 
  further 
  inconsistency 
  that 
  in 
  the 
  

   different 
  families 
  of 
  the 
  Eudoxiae, 
  which 
  are 
  characterized 
  by 
  

   the 
  form 
  of 
  the 
  hydrophylliaj 
  of 
  the 
  gonocalyces 
  and 
  special 
  

   calyces, 
  Eudoxiae 
  are 
  united 
  which 
  originate 
  partly 
  from 
  

   Monopliyidae 
  and 
  partly 
  from 
  Diphyidae. 
  As, 
  further, 
  nearly 
  

   allied 
  species 
  present 
  sometimes 
  liberable, 
  sometimes 
  perma- 
  

   nently 
  sessile 
  Eudoxiae, 
  1 
  prefer 
  to 
  avoid 
  an 
  unnecessary 
  com- 
  

   plication 
  of 
  the 
  system 
  and 
  treat 
  of 
  the 
  Eudoxiae 
  along 
  with 
  

   their 
  parent-colonies. 
  

  

  Family 
  I. 
  Monophyidae, 
  Claus. 
  

  

  Huxley 
  was 
  the 
  first 
  to 
  describe 
  and 
  figure 
  recognizably 
  a 
  

   Monophyid 
  under 
  the 
  name 
  of 
  Spltceronectes. 
  It 
  possesses 
  

  

  