﻿532 
  

  

  PROP. 
  F. 
  SCHMIDT 
  ON 
  THE 
  SILURIAN 
  STRATA 
  

  

  monograph 
  will 
  comprise 
  the 
  Lichadse, 
  Calymenidse, 
  Acidaspidae, 
  

   and 
  some 
  other 
  small 
  groups, 
  leaving 
  the 
  largest 
  group, 
  the 
  Asa- 
  

   phidoe 
  (about 
  40 
  species), 
  to 
  the 
  third 
  and 
  last 
  part. 
  I 
  try 
  to 
  follow 
  

   every 
  genus 
  through 
  the 
  different 
  stages 
  and 
  to 
  investigate 
  the 
  

   changes 
  undergone 
  by 
  it 
  during 
  the 
  development 
  of 
  Silurian 
  life. 
  

  

  The 
  accompanying 
  map 
  (PL 
  XXIII.) 
  is 
  constructed 
  on 
  the 
  scale 
  of 
  

   1 
  : 
  1,500000, 
  the 
  same 
  as 
  that 
  proposed 
  by 
  the 
  Geological 
  Congress 
  for 
  

   the 
  new 
  international 
  geological 
  map 
  of 
  Europe. 
  1 
  have 
  marked 
  on 
  

   the 
  map 
  not 
  only 
  the 
  three 
  great 
  divisions 
  of 
  our 
  Silurian, 
  but 
  also 
  

   the 
  zones 
  from 
  A 
  to 
  K, 
  and 
  some 
  of 
  the 
  subzones, 
  so 
  far 
  as 
  these 
  

   subzones 
  can 
  be 
  traced. 
  The 
  names 
  on 
  the 
  map 
  represent 
  some 
  of 
  

   the 
  most 
  important 
  geological 
  localities. 
  

  

  List 
  of 
  the 
  Described 
  Species 
  of 
  Phacopidce, 
  Cheiruridce, 
  and 
  Encri- 
  

   niiridce 
  of 
  the 
  Silurian 
  Rocks 
  of 
  the 
  Baltic 
  Provinces, 
  arranged 
  

   in 
  accordance 
  with 
  Salter's 
  Monograph 
  of 
  British 
  Trilobites. 
  

  

  

  1 
  

  

  

  C. 
  

  

  1). 
  

  

  E. 
  

  

  F. 
  

  

  G. 
  

  

  II. 
  

  

  I. 
  

  

  K 
  

  

  Abroad. 
  

  

  2 
  

  

  3 
  

  

  1 
  

  

  2 
  

  

  3 
  

  

  i. 
  phacopidj;. 
  

  

  Genus 
  Phacops, 
  Emmr., 
  Salt. 
  

   Subgenus 
  Phacops, 
  Salt. 
  

  

  1. 
  Phacops 
  elegans, 
  Ss. 
  et 
  Boeck 
  

  

  (P. 
  Stokesi, 
  Edu\ 
  pt.) 
  

  

  

  

  

  

  

  

  

  

  * 
  

  

  * 
  

  

  

  * 
  

  

  Gothland, 
  Norway, 
  E. 
  

   Siberia 
  (England 
  ?). 
  

  

  Gothland, 
  England, 
  Po- 
  

   dolia. 
  

  

  Sweden 
  ( 
  Orthoceras- 
  

   limestone). 
  

  

  Sweden 
  (with 
  the 
  for- 
  

   mer). 
  

  

  Prussia, 
  erratics. 
  

  

  Prussia, 
  erratics; 
  

   Prussia, 
  erratics. 
  

  

  Subgenus 
  Acaste, 
  Salt 
  

  

  2. 
  P. 
  Downingise, 
  Murch. 
  (P. 
  

   breviceps,^!;///. 
  See 
  Lindstroni, 
  

   the 
  syn. 
  omitted 
  in 
  the 
  text 
  ot 
  

   the 
  memoir) 
  

  

  

  

  

  

  

  

  

  

  Subgenus 
  Pten/ffometopus, 
  mini. 
  

  

  Supports 
  of 
  the 
  frontal 
  lobe 
  

   crossed 
  by 
  the 
  facial 
  suture. 
  The 
  

   type 
  is 
  P. 
  sclerops, 
  Dalm. 
  Eng- 
  

   lish 
  species 
  are 
  P. 
  alifrms, 
  Salt,, 
  

   and 
  perhaps 
  also 
  P. 
  Uanvimensis, 
  

   Hicks. 
  

   3. 
  P. 
  sclerops, 
  Dalm 
  

  

  * 
  

  

  * 
  

  

  * 
  

  

  

  

  

  

  

  

  

  

  

  4. 
  P. 
  trigonocephala, 
  mihi 
  

  

  

  

  

  

  

  

  

  

  

  

  5. 
  P. 
  Panderi, 
  mihi 
  

  

  

  

  * 
  

  

  

  # 
  

  

  * 
  

  

  

  

  

  

  

  

  6. 
  P. 
  exilis, 
  Eichw 
  

  

  

  

  

  7. 
  P. 
  laevigata, 
  mihi 
  

  

  

  

  

  8. 
  P. 
  kuckersiana, 
  mihi 
  

  

  

  

  

  * 
  

  

  

  

  

  

  

  

  

  9. 
  P. 
  kegelensis, 
  mihi 
  

  

  

  

  

  10. 
  P. 
  Meszkowskii, 
  mihi 
  

  

  

  

  

  

  

  * 
  

  

  

  

  

  

  

  Subgenus 
  Chasmops, 
  M'Coy. 
  

   11. 
  P. 
  ingrica, 
  mihi 
  

  

  

  

  -::- 
  

   * 
  

   * 
  

  

  

  

  

  

  

  

  

  

  12. 
  P. 
  nasuta, 
  mihi 
  

  

  

  

  13. 
  P. 
  prtecurrens, 
  mihi 
  

  

  

  

  

  

  

  