﻿BIHAXG 
  TILL 
  K. 
  SV. 
  VET.-AKAD. 
  HANDL. 
  BAND. 
  6. 
  N:0 
  13. 
  13 
  

  

  the 
  apertural 
  börder 
  short, 
  coBcave, 
  tlie 
  veutral 
  margin 
  paralleL 
  

   to 
  tlie 
  axis 
  of 
  the 
  hydrosoraa; 
  denticle 
  well 
  marked. 
  The 
  

   Gommou 
  canal 
  occupies 
  a 
  third 
  of 
  the 
  breadth 
  of 
  the 
  hydro- 
  

   soma. 
  Hydrothecae, 
  inclined 
  to 
  the 
  axis 
  at 
  an 
  angle 
  of 
  10 
  

   degrees. 
  

  

  Although 
  there 
  is 
  some 
  uncertaiuty 
  aboiit 
  Hisinger's 
  

   tvpe-speciraen, 
  it 
  may 
  however 
  be 
  discovered, 
  that 
  it 
  is 
  the 
  

   same 
  species 
  to 
  which 
  Lapworth, 
  as 
  above 
  stated, 
  is 
  referring. 
  

   Seen 
  in 
  a 
  certain 
  light 
  there 
  are 
  signs 
  of 
  the 
  interiör 
  margin 
  

   of 
  the 
  theca; 
  the 
  convex, 
  exteriör 
  margin 
  is, 
  upon 
  the 
  whole, 
  

   parallel 
  to 
  the 
  dorsal 
  margin. 
  

  

  The 
  specimen 
  exhibits 
  a 
  feeble 
  ventral 
  curvature, 
  yet 
  a 
  

   similar 
  one 
  has 
  also 
  been 
  observed 
  on 
  good 
  specimens 
  from 
  

   other 
  localities. 
  

  

  The 
  figures 
  8- 
  and 
  9, 
  Pl. 
  II, 
  represent 
  Hisingek's 
  type 
  

   specimen 
  in 
  natural 
  and 
  magnified 
  size. 
  For 
  comparison 
  is 
  in 
  

   addition 
  a 
  Scottish 
  specimen 
  figured, 
  PL 
  II, 
  fig. 
  9, 
  coUected 
  by 
  

   Lapworth 
  at 
  Dobbs 
  Linn 
  and 
  wholly 
  transformed 
  to 
  iron 
  pyrite. 
  

  

  This 
  species 
  is 
  found, 
  not 
  only 
  in 
  Dalecarlia, 
  but 
  at 
  

   Kougslena 
  and 
  on 
  Mösseberg 
  in 
  Vestrogothia, 
  also 
  at 
  Eö- 
  

   stånga 
  and 
  some 
  other 
  places 
  in 
  Scania, 
  always 
  in 
  a 
  constant 
  

   horizon, 
  together 
  with 
  M. 
  lohifer, 
  M. 
  convolutiis, 
  M. 
  commiinis, 
  

   Diplograptus 
  folium, 
  Cliviacograptus 
  scalaris, 
  Rastrites 
  pere- 
  

   grinus 
  and 
  others. 
  

  

  No. 
  4. 
  On 
  the 
  same 
  handspecimen 
  as 
  the 
  foregoing, 
  is 
  

   also 
  the 
  original 
  of 
  Prionotus 
  convolutus, 
  which 
  Hisinger 
  de- 
  

   scribes 
  in 
  the 
  followino; 
  terms: 
  

  

  »Prionotus 
  convolutus 
  spiraliter 
  convolutus, 
  lineam 
  latus, 
  

   compressus, 
  rachide 
  marginali, 
  capillari, 
  altero 
  latere 
  dentato, 
  

   dentibus 
  ad 
  basin 
  usque 
  distinctis, 
  lanceolatis, 
  acutiusculis. 
  — 
  

   Icon. 
  Petrif. 
  suec. 
  Suppl., 
  Tab. 
  XXXV, 
  fig. 
  7. 
  Loc. 
  In 
  schisto 
  

   argillaceo 
  ad 
  Furudal, 
  Dalecarliae, 
  cum 
  praecedenti. 
  Museum 
  

   uostrum.» 
  

  

  On 
  the 
  same 
  piece 
  of 
  shale 
  there 
  are 
  several 
  proximal 
  

   fragments 
  of 
  this 
  species. 
  From 
  Dalecarlia 
  I 
  do 
  not 
  know 
  

   any 
  distal 
  portions, 
  whereas 
  complete 
  specimens 
  are 
  found 
  at 
  

   Kongslena 
  as 
  well 
  as 
  at 
  Röstånga, 
  and 
  the 
  species 
  proves 
  it- 
  

   self, 
  by 
  comparing 
  it 
  with 
  figures 
  and 
  descriptions 
  by 
  Lap- 
  

   worth, 
  to 
  be 
  the 
  form, 
  which 
  he 
  denominates 
  Monogr. 
  convo- 
  

   lutus^ 
  var. 
  spiralis. 
  

  

  