﻿554 
  Mr. 
  R. 
  W. 
  Hooley 
  on 
  the 
  

  

  tlie 
  radius 
  rested, 
  bordered 
  postaxially 
  by 
  the 
  longitudinal 
  

   ridge. 
  The 
  ventral 
  surface 
  is 
  strongly 
  convex. 
  On 
  the 
  

   articulation 
  there 
  is 
  clearly 
  visible, 
  although 
  filled 
  with 
  

   matrix, 
  the 
  circular 
  pit 
  near 
  the 
  preaxial 
  border, 
  for 
  the 
  

   hemispherical 
  knob 
  of 
  the 
  proxiuud 
  carpal, 
  and 
  at 
  the 
  post- 
  

   axial 
  edge 
  on 
  the 
  ventral 
  surface 
  are 
  seen 
  the 
  remains 
  of 
  the 
  

   facet 
  for 
  articulation 
  with 
  the 
  produced 
  border 
  of 
  the 
  carpal. 
  

   Distally 
  no. 
  2 
  is 
  very 
  much 
  inflated. 
  

  

  J. 
  a. 
  10, 
  3 
  : 
  the 
  distal 
  end 
  of 
  left 
  ulna. 
  The 
  surface 
  for 
  

   the 
  radius 
  is 
  more 
  concave 
  and 
  the 
  ridge 
  more 
  developed 
  

   than 
  in 
  no. 
  1. 
  The 
  dorsal 
  surface 
  becomes 
  flatter 
  proxi- 
  

   mally, 
  while 
  in 
  nos. 
  1, 
  2, 
  and 
  9 
  it 
  is 
  gently 
  convex. 
  The 
  

   distal 
  extremity 
  of 
  this 
  example 
  differs 
  considerably 
  from 
  

   no. 
  1 
  ; 
  instead 
  of 
  being 
  strongly 
  inflated, 
  both 
  dorsal 
  and 
  

   ventral 
  surfaces 
  are 
  flat, 
  converging 
  and 
  forming 
  an 
  angle 
  

   on 
  the 
  preaxial 
  border. 
  Nos. 
  4, 
  7, 
  8, 
  and 
  1 
  1 
  are 
  examples 
  of 
  

   this 
  type. 
  J. 
  a. 
  10, 
  6, 
  the 
  distal 
  end 
  of 
  left 
  ulna, 
  has 
  a 
  very 
  

   inflated 
  convex 
  ventral 
  surface, 
  continued 
  to 
  ttie 
  articulation. 
  

   The 
  longitudinal 
  ridge 
  is 
  moderately 
  developed. 
  The 
  dorsal 
  

   articular 
  surface 
  for 
  the 
  radius 
  is 
  slightly 
  concave. 
  The 
  

   preaxial 
  side 
  of 
  the 
  articulation 
  is 
  not 
  as 
  inflated 
  as 
  no. 
  I 
  

   nor 
  as 
  compressed 
  and 
  angular 
  as 
  no. 
  3. 
  Nos. 
  5 
  and 
  10 
  are 
  

   examples 
  of 
  this 
  type. 
  

  

  No 
  pneumatic 
  foramina 
  are 
  to 
  be 
  found 
  on 
  any 
  of 
  these 
  

   specimens. 
  

  

  Conclusions 
  as 
  to 
  the 
  Extremities 
  of 
  U/me 
  (see 
  pp. 
  552-553). 
  

  

  By 
  a 
  comparison 
  of 
  the 
  articulatory 
  surfaces 
  of 
  J. 
  a. 
  11, 
  

   1, 
  2, 
  3, 
  4, 
  5, 
  and 
  6, 
  it 
  is 
  quite 
  possible 
  that 
  they 
  belong 
  to 
  

   species 
  with 
  the 
  same 
  type 
  of 
  the 
  distal 
  end 
  of 
  humerus 
  as 
  

   nos. 
  21 
  and 
  32 
  on 
  tablet 
  J. 
  a. 
  6, 
  and 
  therefore 
  of 
  Group 
  A. 
  

   Granting 
  that 
  the 
  proximal 
  ends, 
  J. 
  a. 
  9, 
  2, 
  3, 
  4, 
  5, 
  and 
  (), 
  

   Grotip 
  B, 
  have 
  lost 
  no 
  epiphysis, 
  and 
  aVe 
  as 
  they 
  were 
  in 
  

   life, 
  we 
  consider 
  them 
  to 
  belong 
  to 
  the 
  same 
  reptiles, 
  

   possessing 
  the 
  type 
  of 
  humerus 
  exemplified 
  in 
  the 
  distal 
  end 
  

   of 
  humerus 
  J. 
  a. 
  6, 
  20, 
  Group 
  B, 
  and 
  thus, 
  if 
  our 
  conclusions 
  

   are 
  coirect, 
  to 
  Omit 
  host 
  oma. 
  

  

  The 
  only 
  distal 
  ends 
  of 
  humeri 
  that 
  J. 
  a. 
  9, 
  1, 
  Group 
  C, 
  

   could 
  in 
  any 
  way 
  articulate 
  with 
  are 
  those 
  of 
  the 
  Group 
  C, 
  

   of 
  which 
  the 
  humerus 
  J. 
  a. 
  6, 
  30 
  is 
  the 
  type. 
  The 
  proximal 
  

   end 
  of 
  the 
  ulna 
  J. 
  a. 
  11, 
  7 
  must 
  for 
  the 
  present 
  remain 
  an 
  

   isolated 
  bone, 
  necessitating 
  the 
  formation 
  of 
  Group 
  D, 
  of 
  

   which 
  it 
  is 
  the 
  only 
  example. 
  

  

  There 
  is 
  no 
  evidence 
  available 
  to 
  enable 
  the 
  apportionment 
  

   of 
  any 
  of 
  the 
  distal 
  ends 
  to 
  either 
  of 
  the 
  genera 
  formed 
  by 
  

  

  