﻿534 
  Mr. 
  E. 
  \V. 
  Tlooley 
  on 
  the 
  

  

  It 
  appears 
  tliat 
  different 
  families 
  possessed 
  the 
  pectoral 
  

   girdle 
  cliaracteristic 
  of 
  Oniithostumu 
  {Pterunodon), 
  e. 
  g., 
  

   Ornithodesmus, 
  but 
  the 
  form 
  o£ 
  the 
  skull, 
  the 
  position 
  and 
  

   sJiape 
  of 
  the 
  several 
  elements^ 
  the 
  absence 
  or 
  presence^ 
  size, 
  

   and 
  position 
  of 
  the 
  teeth, 
  vai 
  y 
  in 
  the 
  different 
  genera, 
  and 
  

   are 
  therefore 
  tlie 
  characters 
  most 
  to 
  be 
  triisted 
  in 
  classifica- 
  

   tion. 
  By 
  such 
  means 
  the 
  portions 
  of 
  skulls 
  included 
  in 
  tlie 
  

   Cambridge 
  material 
  under 
  the 
  genus 
  Ornithocheirus 
  natu- 
  

   rally 
  divide 
  into 
  five 
  well-defined 
  groups, 
  and 
  it 
  is 
  more 
  than 
  

   probable 
  that 
  they 
  belong 
  but 
  to 
  few 
  species. 
  The 
  humeri 
  

   and 
  ulnffi 
  may 
  be 
  arranged 
  into 
  three 
  groups. 
  

  

  Further, 
  Seeley 
  * 
  was 
  misled 
  by 
  a 
  study 
  of 
  the 
  German 
  

   specimens 
  in 
  determining 
  the 
  ulna 
  as 
  tlie 
  radius 
  and 
  the 
  

   radius 
  as 
  the 
  ulna, 
  and 
  therefore 
  the 
  wrong 
  position 
  of 
  these 
  

   bones 
  in 
  the 
  antebrachium 
  and 
  their 
  place 
  of 
  articulation 
  

   with 
  the 
  proximal 
  carpal, 
  and 
  in 
  stating 
  that 
  the 
  radius 
  was 
  

   the 
  larger 
  bone. 
  

  

  He 
  was 
  studying 
  extremely 
  fragmentary 
  remains, 
  and 
  in 
  

   the 
  German 
  specimens 
  the 
  bones 
  are 
  so 
  crushed 
  that 
  the 
  

   detailed 
  structure 
  of 
  their 
  articulations 
  is 
  nearly 
  indecipher- 
  

   able. 
  

  

  We 
  shall 
  now 
  proceed 
  to 
  denote 
  the 
  characters 
  by 
  which 
  

   the 
  fragments 
  of 
  snouts 
  may 
  be 
  classified, 
  and 
  give 
  the 
  

   species 
  "which 
  naturally 
  group 
  themselves 
  under 
  each. 
  

   Many 
  of 
  the 
  specimens 
  are 
  so 
  close 
  to 
  one 
  another 
  — 
  which 
  

   is 
  remarkable 
  in 
  itself, 
  considering 
  their 
  fragmentary 
  state 
  

   - 
  — 
  tliat 
  the 
  differences 
  in 
  detail, 
  which 
  are 
  often 
  trivial, 
  are 
  

   of 
  little 
  avail 
  until 
  future 
  discoveries 
  of 
  more 
  complete 
  skulls 
  

   exhibit 
  otherwise. 
  This, 
  we 
  are 
  confident 
  from 
  a 
  close 
  study 
  

   of 
  these 
  specimens, 
  will 
  not 
  be 
  the 
  case, 
  and 
  it 
  is 
  strange 
  

   tliat 
  every 
  specimen 
  found 
  should 
  have 
  belonged 
  to 
  a 
  new 
  

   species. 
  The 
  twenty-six 
  ty[)e-specimens 
  in 
  the 
  Sedgwick 
  

   Museum 
  have 
  been 
  described 
  by 
  Seeley 
  or 
  Owen 
  ; 
  therefore 
  

   it 
  will 
  not 
  be 
  necessary 
  to 
  do 
  that 
  again. 
  

  

  Group 
  No. 
  1. 
  

  

  Beaks 
  laterally 
  compressed, 
  moderate 
  vertical 
  depth, 
  tip 
  

   more 
  or 
  less 
  obtuse, 
  dorsal 
  keels. 
  Palate 
  curving 
  slightly 
  

   upwards 
  anteriorly, 
  causing 
  the 
  front 
  teeth 
  to 
  be 
  directed 
  

   forward. 
  Longitudinal 
  ridge 
  on 
  palate, 
  teeth 
  subcircular, 
  

   alveolar 
  rims 
  rising 
  above 
  palate. 
  

  

  * 
  II. 
  G. 
  Seeley, 
  ' 
  Ornithosauiin,' 
  1870, 
  p, 
  42. 
  

  

  