﻿OP 
  THE 
  WENLOCK 
  SHALES. 
  387 
  

  

  According 
  to 
  Prof. 
  Nicholson, 
  " 
  The 
  restricted 
  genus 
  Tentaculites 
  

   may 
  be 
  defined 
  as 
  including 
  small 
  shells 
  which 
  have 
  the 
  form 
  of 
  

   straight 
  conical 
  tubes, 
  tapering 
  towards 
  one 
  extremity 
  to 
  a 
  pointed 
  

   closed 
  apex, 
  and 
  expanding 
  towards 
  the 
  other 
  to 
  a 
  rounded 
  aper- 
  

   ture. 
  The 
  shell 
  is 
  free 
  ; 
  and 
  its 
  walls 
  are 
  thin, 
  and 
  are 
  surrounded 
  

   by 
  numerous 
  thickened 
  rings 
  or 
  annulations." 
  I 
  have 
  no 
  evidence 
  

   for 
  the 
  latter 
  clause 
  of 
  Prof. 
  Nicholson's 
  restricted 
  types 
  ; 
  and 
  I 
  

   cannot 
  therefore 
  adopt 
  it 
  in 
  this 
  paper. 
  His 
  words 
  are 
  these 
  : 
  — 
  

   " 
  sometimes 
  with 
  intermediate 
  strice 
  over 
  the 
  whole 
  or 
  part 
  of 
  the 
  length 
  

   of 
  the 
  tithe 
  " 
  * 
  

  

  This 
  part 
  of 
  the 
  above 
  is 
  for 
  the 
  purpose 
  of 
  including 
  the 
  peculiar 
  

   species 
  of 
  Salter 
  ; 
  and 
  to 
  prevent 
  any 
  misconception, 
  I 
  reproduce 
  the 
  

   bibliography 
  of 
  this 
  remarkable 
  type. 
  

  

  7. 
  Tentaculites 
  anglicus, 
  Salter, 
  Siluria, 
  2nd 
  ed. 
  pi. 
  i. 
  fig. 
  3. 
  

  

  Straight, 
  unattached, 
  worm-tubes, 
  resembling 
  some 
  horny 
  Medi- 
  

   terranean 
  species 
  ; 
  and 
  still 
  more 
  like 
  the 
  Cormdites 
  serpidarius 
  of 
  

   the 
  Wenlock 
  and 
  Dudley 
  Eocks 
  (Cambr. 
  Cat. 
  p. 
  47). 
  

  

  T. 
  scalaris, 
  Schl., 
  Sil. 
  Syst. 
  pi. 
  xix. 
  fig. 
  15. 
  

  

  T. 
  scalaris, 
  Schl. 
  Llandovery 
  species, 
  internal 
  cast 
  of 
  T. 
  anglicus 
  

   (Salter, 
  Siluria, 
  p. 
  221). 
  

  

  T. 
  annulatus, 
  Schl., 
  Sil. 
  pi. 
  x. 
  figs. 
  2 
  and 
  3 
  (ed. 
  1859). 
  

  

  T. 
  anglicus, 
  Salter 
  (Siluria, 
  3rd 
  ed. 
  pi. 
  i. 
  fig. 
  3) 
  ; 
  T. 
  anmdatas^ 
  

   Sil. 
  Syst. 
  The 
  T. 
  annidatus 
  is 
  a 
  Devonian 
  form 
  without 
  the 
  fine 
  

   longitudinal 
  striae 
  (Salter, 
  Cambr. 
  Catalogue, 
  p. 
  76). 
  

  

  T. 
  annidatus, 
  Salter, 
  fig. 
  547; 
  Lyell, 
  Elem. 
  of 
  Geology, 
  ed. 
  

   1871 
  (fig. 
  553, 
  ed. 
  1878). 
  

  

  " 
  Of 
  the 
  sixteen 
  species 
  of 
  Annelida 
  only 
  two 
  pass 
  to 
  the 
  Lower 
  

   and 
  Upper 
  Llandovery, 
  T, 
  anglicus 
  and 
  Cormdites 
  serpularius. 
  They 
  

   range 
  also 
  to 
  the 
  Ludlow." 
  — 
  (Mr.Etheridge's 
  Presid. 
  Address, 
  p. 
  108.) 
  

  

  I 
  cannot 
  identify 
  the 
  species 
  in 
  any 
  of 
  the 
  Wenlock-Shale 
  wash- 
  

   ings. 
  If 
  Salter's 
  figures 
  are 
  to 
  be 
  relied 
  upon, 
  the 
  nearest 
  approach 
  

   to 
  the 
  type 
  is 
  Cormdites 
  scalariformis 
  (see 
  ante, 
  pp. 
  379, 
  380) 
  ; 
  but 
  

   this 
  species 
  is 
  attached, 
  and 
  not 
  free, 
  as 
  T. 
  anglicus 
  is 
  said 
  to 
  be. 
  

  

  8. 
  Tentaculites 
  ornatus, 
  Sowerby. 
  

  

  Type, 
  'Siluria,' 
  fig. 
  11, 
  plate 
  xvi., 
  especially 
  the 
  section 
  magnified. 
  

  

  ? 
  T. 
  annidatus, 
  His. 
  Lethsea 
  Suecica, 
  pi. 
  xxxv. 
  fig. 
  2 
  (1837). 
  

  

  Tube 
  delicate, 
  elongated, 
  free, 
  varying 
  in 
  length, 
  but 
  of 
  unknown 
  

   dimensions 
  as 
  regards 
  the 
  fragmentary 
  condition 
  of 
  specimens 
  found 
  

   in 
  the 
  shales. 
  Superior 
  annulations 
  placed 
  at 
  varying 
  distances, 
  

   about 
  three 
  to 
  aline, 
  spaces 
  between 
  marked 
  by 
  inferior 
  annulations. 
  

   Walls 
  of 
  tube 
  thin, 
  the 
  hollow 
  interior 
  about 
  two 
  thirds 
  the 
  diame- 
  

   ter 
  of 
  the 
  tube, 
  which, 
  towards 
  the 
  distal 
  extremity, 
  is 
  about 
  half 
  a 
  

   line. 
  The 
  annulations 
  at 
  the 
  proximal 
  part 
  of 
  the 
  tube, 
  for 
  about 
  

   a 
  line 
  and 
  a 
  half 
  from 
  base, 
  about 
  5 
  to 
  a 
  line. 
  

  

  Loc. 
  Coalbrookedale 
  beds, 
  no. 
  43, 
  rare 
  ; 
  Tickwood 
  beds, 
  no. 
  25, 
  

  

  * 
  Geological 
  Mag. 
  Oct. 
  1872. 
  Italics 
  mine. 
  

  

  