﻿IKEDALE 
  : 
  ON 
  MISAPPLIED 
  GKNEKIC 
  NAMES. 
  255 
  

  

  Accepting 
  Solarium 
  lifrons 
  as 
  the 
  type 
  of 
  Omalaxis, 
  he 
  noted 
  it 
  differed 
  

   conchologically 
  from 
  Lea's 
  Orbis 
  rotella 
  and 
  Yerrill's 
  Omalaxis 
  nobilis, 
  

   whilst 
  these 
  agreed 
  in 
  shell 
  characters 
  with 
  Fischer's 
  ^ 
  zanclcea', 
  

   but 
  the 
  opercular 
  characters 
  of 
  the 
  two 
  latter 
  were 
  known 
  to 
  be 
  

   different. 
  Arguing 
  that 
  the 
  American 
  fossil 
  and 
  recent 
  forms 
  might 
  

   be 
  allied, 
  and 
  that 
  the 
  European 
  fossil 
  and 
  recent 
  forms 
  went 
  together, 
  

   lie 
  suggested 
  a 
  new 
  name 
  Discosolis 
  for 
  the 
  American 
  forms, 
  indicating 
  

   Verrill's 
  0. 
  nobilis 
  as 
  type, 
  and 
  subordinated 
  this 
  to 
  Dunker's 
  genus 
  

   JDiscohelix, 
  introduced 
  for 
  a 
  European 
  Lias 
  fossil. 
  It 
  appeared 
  from 
  

   the 
  statement 
  tliat 
  Dall 
  advised 
  the 
  rejection 
  of 
  Omalaxis 
  for 
  shells 
  

   like 
  0. 
  nobilis, 
  Verrill, 
  yet 
  in 
  1900 
  Dall 
  and 
  Simpson, 
  writing 
  on 
  the 
  

   Mollusca 
  of 
  Porto 
  llico"^ 
  (Bull. 
  Eish. 
  Comm., 
  1900, 
  p. 
  432, 
  pi. 
  liv, 
  

   fig. 
  12), 
  described 
  Omalaxis 
  exquisita, 
  a 
  species 
  conchologically 
  

   comparable 
  with 
  0. 
  nobilis, 
  Verrill. 
  

  

  Saceo 
  (I 
  Melius. 
  Terr. 
  Terz. 
  Piemonte, 
  pt. 
  xii, 
  p. 
  75, 
  1892) 
  used 
  

   genericall}' 
  Biscohelix 
  and 
  subgenerically 
  Pseudomalaxis 
  for 
  fossils 
  

   agreeing 
  closely 
  with 
  the 
  true 
  B. 
  ? 
  zanclma, 
  Philippi, 
  whilst 
  in 
  the 
  

   Iconograpliia, 
  Cossmann 
  and 
  Pissarro, 
  Biscohelix 
  is 
  used 
  for 
  a 
  shell 
  

   apparently 
  like 
  the 
  true 
  B. 
  '^zanclcea, 
  Philippi, 
  and 
  another 
  fossil 
  

   is 
  referred 
  to 
  the 
  subgenus 
  Pseudomalaxis 
  of 
  Biscohelix. 
  This 
  usage 
  

   is, 
  of 
  course, 
  due 
  to 
  the 
  confusion 
  of 
  the 
  recent 
  with 
  the 
  fossil 
  shell 
  ; 
  

   a 
  geological 
  student 
  being 
  conversant 
  with 
  the 
  latter 
  and 
  regarding 
  it 
  

   as 
  the 
  type 
  of 
  Pseudomalaxis, 
  whilst, 
  as 
  I 
  have 
  pointed 
  out, 
  the 
  recent 
  

   sliell, 
  now 
  called 
  P. 
  Macandreivi, 
  Iredale, 
  must 
  be 
  considered 
  the 
  type, 
  

   and 
  the 
  genus 
  restricted 
  to 
  shells 
  agreeing 
  in 
  character 
  with 
  that 
  

   species. 
  Before 
  epitomizing 
  my 
  conclusions 
  I 
  wish 
  to 
  make 
  a 
  few 
  

   remarks 
  about 
  some 
  shells 
  described 
  as 
  Bifrontia 
  or 
  Omalaxis. 
  

  

  When 
  Dall 
  introduced 
  Biscosolis 
  he 
  described 
  a 
  new 
  species 
  as 
  

   Biscohelix 
  {Biscosolis) 
  retifera 
  (loc. 
  cit., 
  p. 
  332, 
  pi. 
  xix, 
  figs. 
  \b, 
  c, 
  

   1892). 
  I 
  can 
  see 
  no 
  characters 
  separating 
  that 
  species 
  from 
  Heliacus. 
  

   Harris 
  (Cat. 
  Tert. 
  Moll. 
  Brit. 
  Mus., 
  vol. 
  i, 
  p. 
  245) 
  has 
  pointed 
  out 
  

   that 
  Torinia, 
  Gray, 
  was 
  a 
  nude 
  name 
  until 
  after 
  Heliacus 
  had 
  been 
  

   properly 
  introduced 
  by 
  D'Orbigny 
  (Pamon 
  de 
  la 
  Sagra, 
  Nat. 
  Hist, 
  

   d'ile 
  de 
  Cuba, 
  vol. 
  i, 
  p. 
  68, 
  1842) 
  ; 
  and 
  two 
  flattened 
  species, 
  

   H. 
  disGoideus, 
  Pease, 
  and 
  H. 
  ccelatus, 
  Hinds, 
  show 
  juveniles 
  agreeing 
  

   with 
  B. 
  retifera, 
  Dall, 
  in 
  every 
  conchological 
  character. 
  A 
  very 
  

   similar 
  shell 
  has 
  been 
  described 
  by 
  Melvill 
  as 
  Solarium 
  {Torinia) 
  

   omalaxis. 
  

  

  Melvill 
  and 
  Standen 
  (Ann. 
  Mag. 
  Nat. 
  Hist., 
  vol. 
  xii, 
  pp. 
  298, 
  299, 
  

   1903) 
  introduced 
  two 
  new 
  species 
  of 
  Homalaxis, 
  as 
  cornu-ammonis 
  oxiH 
  

   rotula-catherina, 
  and 
  wrote: 
  "We 
  cannot 
  exactly 
  follow 
  the 
  reasons 
  

   Avhich 
  prompt 
  Dr. 
  Fischer 
  (Manuel 
  de 
  Conch., 
  p. 
  714) 
  to 
  propose 
  

   a 
  subgenus 
  Pseudomalaxis 
  for 
  H. 
  zanclea, 
  Phil., 
  and 
  consider 
  all 
  the 
  

   true 
  Homalaxis, 
  Desh., 
  tertiary 
  fossils. 
  In 
  our 
  opinion 
  both 
  the 
  

   species 
  now 
  described 
  belong 
  to 
  the 
  typical 
  genus, 
  and 
  it 
  would 
  be 
  

   impossible 
  to 
  disassociate 
  H. 
  Pernambneensis 
  (Wats.), 
  described 
  as 
  

   a 
  Bifrontia 
  from 
  them." 
  I 
  believe 
  that 
  this 
  statement 
  is 
  based 
  upon 
  

   an 
  examination 
  of 
  the 
  recent 
  ' 
  zanclcea 
  ', 
  as 
  at 
  that 
  time 
  Solarium 
  

   bifrons, 
  Lam., 
  was 
  considered 
  the 
  type 
  of 
  Omalaxis, 
  and 
  this 
  shell 
  is 
  

   very 
  unlike 
  the 
  new 
  species 
  above 
  named. 
  I 
  should 
  place 
  these 
  two 
  

  

  