﻿THE 
  " 
  WEISSER 
  JURA. 
  " 
  OF 
  BAVARIA. 
  167 
  

  

  time 
  this 
  group 
  does 
  present 
  some 
  curious 
  transitional 
  types 
  — 
  e. 
  g. 
  

   Pisocrinus, 
  Triacrinus, 
  and 
  {a/pud 
  W. 
  and 
  S.) 
  Allagecrinus. 
  Ou- 
  

   pressocrinus 
  is 
  a 
  form 
  that 
  endeavours 
  at 
  times 
  to 
  break 
  with 
  old 
  

   traditions, 
  and 
  appears 
  with 
  a 
  triradiate 
  or 
  quinqueradiate 
  stem 
  *. 
  

   To 
  turn 
  to 
  another 
  point 
  : 
  Dr. 
  Carpenter 
  considers 
  the 
  processes 
  of 
  

   the 
  radials 
  in 
  Antedon 
  abyssicola 
  to 
  be 
  of 
  a 
  larval 
  character 
  f; 
  these 
  

   processes 
  are 
  homologous 
  with 
  the 
  petals, 
  spearheads, 
  or 
  spines 
  of 
  

   Eugeniacrinidae 
  ; 
  further 
  they 
  are 
  exactly 
  parallelled 
  in 
  many 
  of 
  the 
  

   Larviformia, 
  see 
  drawing 
  of 
  Haplocrinvs 
  (PI. 
  VI. 
  fig. 
  19). 
  In 
  the 
  

   present 
  state 
  of 
  our 
  knowledge 
  it 
  would 
  not 
  be 
  safe 
  to 
  connect 
  the 
  

   Eugeniacrinidse 
  more 
  closely 
  with 
  these 
  very 
  ancient 
  forms. 
  It 
  

   should, 
  however, 
  be 
  remembered 
  that 
  the 
  division 
  between 
  the 
  so-called 
  

   Palseocrinoidea 
  and 
  JSTeocrinoidea 
  is 
  caused 
  very 
  largely 
  by 
  the 
  gap 
  in 
  

   the 
  record 
  at 
  the 
  close 
  of 
  the 
  Palaeozoic 
  era; 
  these 
  two 
  assemblages 
  are 
  

   admittedly 
  heterogeneous, 
  and 
  cannot, 
  on 
  the 
  face 
  of 
  things, 
  represent 
  

   divergent 
  branches 
  from 
  an 
  ancestral 
  stock. 
  A 
  classification 
  that 
  

   shall 
  adequately 
  represent 
  the 
  true 
  relations 
  or, 
  what 
  comes 
  to 
  the 
  

   same 
  thing, 
  the 
  history 
  of 
  the 
  Crinoidea, 
  is 
  yet 
  to 
  seek. 
  When 
  this 
  

   has 
  been 
  found, 
  the 
  form 
  described 
  in 
  the 
  present 
  paper 
  will 
  fall 
  

   into 
  its 
  true 
  place 
  at 
  the 
  end 
  of 
  a 
  long 
  series 
  ; 
  and 
  to 
  our 
  examples 
  

   of 
  the 
  law 
  that 
  senescent 
  and 
  degenerate 
  forms 
  resemble 
  the 
  ado- 
  

   lescent 
  forms 
  in 
  the 
  early 
  history 
  of 
  the 
  same 
  race, 
  will 
  be 
  added 
  one 
  

   more, 
  viz. 
  Trigonocrinus. 
  

  

  APPENDIX. 
  

  

  Sudden 
  Deviations 
  prom 
  Normal 
  SrMMETRY, 
  chiefly 
  in 
  

   " 
  Neocrinoidea." 
  

  

  Besides 
  the 
  examples 
  given 
  in 
  the 
  body 
  of 
  the 
  paper 
  (p. 
  155), 
  I 
  

   have 
  collected 
  the 
  following 
  instances 
  ; 
  those 
  for 
  which 
  no 
  author 
  is 
  

   quoted 
  are 
  from 
  my 
  personal 
  observations. 
  

  

  Holopus 
  Bangi, 
  d'Orb. 
  Type 
  specimen 
  4-rayed. 
  A. 
  d'Orbigny, 
  

   in 
  Guerin, 
  ' 
  Magasin 
  de 
  Zoologie,' 
  Classe 
  x. 
  pi. 
  iii. 
  Paris, 
  1837. 
  

   Coll 
  . 
  Jardin 
  des 
  Plantes. 
  

  

  Eugeniacrinus 
  caryophyllatus, 
  v. 
  Schloth. 
  A 
  4-rayed 
  calyx, 
  seen 
  

   from 
  above. 
  A. 
  Goldfuss, 
  ' 
  Petrefacta 
  Germanise,' 
  &c, 
  Dusseldorf, 
  

   1826-1833: 
  p. 
  163, 
  pi. 
  1. 
  f. 
  3 
  r. 
  Loo.? 
  Coll. 
  Bonn, 
  Poppelsdorf 
  

   Museum. 
  

  

  Euq, 
  nutans. 
  Goldf. 
  A 
  4-rayed 
  calyx. 
  A. 
  Goldfuss, 
  op. 
  cit. 
  p. 
  164, 
  

   pi. 
  1. 
  f. 
  4, 
  s. 
  Loc. 
  ? 
  Coll. 
  Bonn. 
  

  

  Tetracrinus 
  moniliformis, 
  Miinst., 
  reverts 
  to 
  pentamerous 
  type. 
  P. 
  

   de 
  Loriol, 
  " 
  Monogr. 
  Crinoides 
  Eoss. 
  de 
  la 
  Suisse," 
  3rd 
  part, 
  Abh. 
  

   schweiz. 
  pal. 
  Ges. 
  vi. 
  Geneva, 
  1879 
  : 
  pi. 
  xix. 
  f. 
  39, 
  39 
  a, 
  39 
  b. 
  

   " 
  Article 
  basal 
  qui 
  porte 
  5 
  cotes, 
  ce 
  qui 
  indique 
  5 
  radiales." 
  Loc. 
  

   Oberbuchsitten. 
  Coll. 
  Cartier, 
  in 
  Basle 
  Museum. 
  

  

  * 
  L. 
  Schultze, 
  Monogr. 
  Echinod. 
  Eifl. 
  Kalkes, 
  Denkschr. 
  k. 
  Acacl. 
  Wiss. 
  math- 
  

   nat. 
  Classe, 
  xxvi. 
  pp. 
  113-230 
  (Wien, 
  1867) 
  ; 
  see 
  pi. 
  i. 
  f. 
  2 
  b, 
  2e, 
  3 
  d, 
  and 
  pi. 
  iii. 
  

   f.2i. 
  

  

  t 
  P. 
  H. 
  Carpenter, 
  ' 
  Challenger 
  ' 
  Report, 
  Zoology, 
  vol. 
  xxvi. 
  pait 
  lx. 
  The 
  

   Comatulae. 
  London, 
  1888 
  ; 
  see 
  p. 
  192. 
  

  

  