﻿591 
  Mr. 
  E. 
  L. 
  Clark 
  on 
  the 
  

  

  statement 
  of 
  any 
  case, 
  I 
  shall 
  consider 
  it 
  a 
  great 
  favour 
  to 
  

   be 
  promptly 
  corrected. 
  

  

  In 
  the 
  tenth 
  edition 
  of 
  the 
  ' 
  Systema 
  Naturae' 
  Linne 
  

   includes 
  in 
  his 
  genus 
  Echinus 
  four 
  nominal 
  species 
  (rosaceus, 
  

   reticulatus, 
  placenta, 
  orbiculus), 
  which 
  it 
  is 
  universally 
  agreed 
  

   are 
  clypeastroids. 
  The 
  references 
  and 
  figures 
  which 
  he 
  cites 
  

   under 
  each 
  name 
  show 
  that 
  these 
  species, 
  with 
  the 
  exception 
  

   of 
  placenta, 
  are 
  composite 
  groups, 
  and 
  not 
  species 
  as 
  we 
  

   understand 
  the 
  term 
  to-day. 
  The 
  form 
  named 
  Echinus 
  

   placenta 
  is, 
  however, 
  a 
  well-known 
  East-Indian 
  species, 
  and 
  

   there 
  is 
  not 
  now 
  and 
  never 
  has 
  been 
  any 
  doubt 
  as 
  to 
  its 
  

   identity. 
  The 
  name 
  rosaceus 
  has 
  been 
  the 
  source 
  of 
  much 
  

   confusion, 
  and 
  unfortunately 
  Loven, 
  in 
  his 
  very 
  important 
  

   and 
  valuable 
  work 
  on 
  the 
  Echinoidea 
  described 
  by 
  Linne 
  

   (1887, 
  Bihang 
  Kgl. 
  Svenska 
  Vet.-Akad. 
  Handl. 
  xiii.), 
  has 
  not 
  

   helped 
  matters 
  at 
  all, 
  because, 
  as 
  pointed 
  out 
  by 
  Lambert 
  

   (1905, 
  Ann. 
  Univ. 
  Lyon, 
  n. 
  s. 
  i. 
  p. 
  142), 
  he 
  overlooked 
  

   Lamarck's 
  work 
  published 
  in 
  1801, 
  which 
  has 
  an 
  important 
  

   bearing 
  on 
  the 
  matter. 
  As 
  Loven 
  admits 
  there 
  is 
  no 
  

   authentic 
  type 
  specimen 
  of 
  rosac-Ais, 
  we 
  must 
  judge 
  of 
  the 
  

   species 
  by 
  what 
  is 
  published 
  in 
  the 
  ' 
  Systema 
  Naturae' 
  ; 
  and 
  

   there 
  can 
  be 
  no 
  doubt 
  that 
  the 
  diagnosis 
  and 
  references 
  

   given 
  there 
  (ed. 
  x. 
  p. 
  665) 
  show 
  conclusively 
  that 
  the 
  name 
  

   covers 
  a 
  composite 
  group, 
  including 
  species 
  of 
  Echinanthas, 
  

   Clypeaster, 
  and 
  Laganum, 
  as 
  those 
  genera 
  are 
  used 
  by 
  

   A. 
  Agassiz 
  in 
  the 
  ' 
  Revision 
  of 
  the 
  Echini.' 
  Leske 
  (1778, 
  

   Add. 
  ad 
  Klein) 
  failed 
  to 
  differentiate 
  these 
  various 
  forms 
  

   satisfactorily, 
  but 
  elects 
  to 
  call 
  the 
  group 
  Echinanthus 
  

   humilis, 
  admitting 
  at 
  the 
  start 
  that 
  his 
  name 
  is 
  a 
  synonym 
  

   of 
  rosaceus. 
  Lamarck, 
  however, 
  in 
  1801 
  (Syst. 
  Anim. 
  s. 
  

   Vert. 
  p. 
  342), 
  recognizing 
  the 
  composite 
  nature 
  of 
  rosaceus, 
  

   restricted 
  that 
  name 
  to 
  the 
  West-Indian 
  species 
  called 
  in 
  the 
  

   ' 
  .Revision 
  ' 
  Echinanthus 
  rosaceus, 
  and 
  placed 
  it 
  as 
  the 
  first 
  

   of 
  two 
  species 
  in 
  a 
  new 
  genus, 
  Clypeaster. 
  The 
  other 
  species 
  

   {pentapora) 
  he 
  removed 
  in 
  1816 
  to 
  Scutella, 
  and 
  so 
  rosaceus 
  

   must 
  be 
  the 
  type 
  of 
  Clypeaster. 
  I 
  fully 
  agree 
  with 
  Lambert 
  

   that 
  Loven's 
  attempt 
  to 
  restrict 
  the 
  name 
  rosaceus 
  to 
  the 
  

   " 
  species 
  of 
  the 
  Eastern 
  Seas, 
  commonly 
  named 
  Clypeaster 
  

   placunarius" 
  is 
  not 
  only 
  unconvincing 
  and 
  belated, 
  but 
  is 
  

   most 
  unfortunate. 
  

  

  What, 
  then, 
  becomes 
  of 
  the 
  name 
  Echinanthus 
  ? 
  I 
  regret 
  

   that 
  I 
  cannot 
  answer 
  this 
  question 
  in 
  agreement 
  with 
  either 
  

   Lambert 
  or 
  Duncan. 
  The 
  reason, 
  however, 
  is 
  obvious. 
  

   They 
  both 
  go 
  back 
  to 
  a 
  pre-Linnean 
  authority. 
  Under 
  the 
  

   Code, 
  which 
  I 
  am 
  trying 
  to 
  follow, 
  the 
  fate 
  of 
  Echinanthus, 
  

   Leske, 
  the 
  first 
  post-Linnean 
  writer 
  to 
  use 
  the 
  name, 
  is 
  

  

  