﻿AND 
  AVES 
  OF 
  NORTH 
  AMERICA. 
  166-A 
  

  

  an 
  anterior 
  rib. 
  The 
  axilliary 
  pit 
  is 
  less 
  prominently 
  margined 
  by 
  a 
  high 
  osseons 
  wall, 
  and 
  it 
  is 
  elongate 
  and 
  curved 
  

   forwards, 
  nearly 
  reaching 
  the 
  margin 
  of 
  the 
  bone. 
  The 
  rib 
  head 
  is 
  complete. 
  

  

  With 
  its 
  fellow, 
  it 
  embraces 
  a 
  first 
  vertebral, 
  which 
  is 
  about 
  twice 
  as 
  long 
  as 
  wide 
  and 
  six-sided. 
  The 
  sides 
  are 
  

   in 
  the 
  oi'der 
  of 
  their 
  length: 
  posterior 
  (shortest), 
  anterior, 
  postero-lateral, 
  antero-lateral. 
  The 
  anterior 
  marginal 
  is 
  

   narrow 
  in 
  front. 
  It 
  expands 
  so 
  much 
  posteriorly 
  as 
  to 
  make 
  the 
  first 
  lateral 
  almost 
  triangular. 
  The 
  second 
  marginal 
  

   is 
  nearly 
  quadrate. 
  The 
  edge 
  of 
  these 
  marginals 
  is 
  thin 
  above 
  the 
  nape, 
  and 
  thickens 
  laterally. 
  In 
  the 
  posterior 
  it 
  is 
  

   gradually 
  thinned 
  out 
  and 
  a 
  very 
  little 
  recurved. 
  The 
  second 
  vertebral 
  bone 
  is 
  not 
  so 
  long 
  as 
  broad: 
  those 
  following 
  

   increase 
  gradually 
  in 
  length. 
  

  

  The 
  narrow 
  extent 
  of 
  the 
  hyposternal 
  bone 
  in 
  front 
  of 
  the 
  inguinal 
  crest 
  indicates 
  as 
  in 
  T. 
  molops, 
  an 
  intermar- 
  

   ginal 
  sternal. 
  The 
  sutures 
  retires 
  posteriorly 
  from 
  that 
  point, 
  suggesting 
  the 
  continuation 
  of 
  that 
  bone 
  towards 
  the 
  

   middle 
  line. 
  The 
  caviby 
  of 
  the 
  plastron 
  is 
  extended 
  well 
  laterally 
  at 
  the 
  bridge. 
  The 
  hypo-xiphisternal 
  suture 
  is 
  

   nearly 
  transverse. 
  The 
  pubic 
  scar 
  is 
  little 
  elevated, 
  and 
  broadest 
  posteriorly. 
  Its 
  median 
  crest 
  extends 
  throughout 
  

   the 
  whole 
  length. 
  The 
  posterior 
  margin 
  of 
  the 
  xiphisternal 
  is 
  not 
  preserved. 
  The 
  mesosternum 
  is 
  of 
  a 
  rounded 
  form, 
  

   but 
  obtusely 
  pointed 
  behind, 
  and 
  with 
  lateral 
  rounded 
  projections. 
  The 
  posterior 
  sutures 
  are 
  bevelled 
  forwards 
  and 
  

   upwards. 
  

  

  The 
  sculpture 
  is 
  much 
  like 
  that 
  of 
  Taphrosphys 
  sulcatus. 
  The 
  marginal 
  bones 
  have 
  a 
  delicate 
  transverse 
  reticula- 
  

   tion, 
  and 
  the 
  costals 
  a 
  coarser 
  longitudinal 
  one. 
  The 
  under 
  surfaces 
  do 
  not 
  present 
  any 
  sculpture, 
  perhaps, 
  on 
  account 
  

  

  of 
  corrosive 
  action. 
  

  

  M. 
  

  

  Length 
  of 
  last 
  costal, 
  .08 
  

  

  " 
  iliac 
  pit, 
  .02 
  

  

  " 
  pubic 
  scar, 
  .024 
  

  

  " 
  third 
  costal 
  bone, 
  .106 
  

  

  Width 
  third 
  (costal 
  bone 
  proximally), 
  .0242 
  

  

  (distally), 
  .026 
  

  

  Thickness 
  " 
  " 
  (proximally), 
  .007 
  

  

  " 
  " 
  " 
  (distally), 
  .0025 
  

  

  Width 
  first 
  " 
  (greatest), 
  .094 
  

  

  Length 
  " 
  vertebral, 
  .039 
  

  

  Width 
  ! 
  < 
  " 
  .0182 
  

  

  "second 
  " 
  .02' 
  

  

  Length 
  " 
  " 
  .02 
  

  

  Length 
  median 
  marginal, 
  .068 
  

  

  Width 
  " 
  " 
  (anterior), 
  .0327 
  

  

  " 
  " 
  " 
  (posterior), 
  .063 
  

  

  " 
  hyposternal, 
  .063 
  

  

  Thickness 
  " 
  .004 
  

  

  Length 
  " 
  .092 
  

  

  " 
  mesosternal, 
  .0305 
  

   Width 
  " 
  .0315 
  

   The 
  dermal 
  scuta 
  have 
  been 
  thin, 
  as 
  in 
  other 
  species 
  of 
  this 
  group. 
  The 
  sutures 
  are 
  all 
  straight 
  except 
  that 
  be- 
  

   tween 
  the 
  first 
  and 
  second 
  vertebrals, 
  which 
  is 
  convex 
  backwards. 
  The 
  vertebrals 
  are 
  broader 
  than 
  long, 
  and 
  their 
  

   external 
  angle 
  is 
  near 
  the 
  middle 
  of 
  the 
  length 
  of 
  the 
  costal 
  bones. 
  The 
  anterior 
  vertebral 
  is 
  of 
  longer 
  form 
  than 
  the 
  

   others, 
  somewhat 
  like 
  the 
  frustrum 
  of 
  a 
  triangle, 
  of 
  which 
  the 
  base 
  is 
  anterior. 
  The 
  second 
  marginal 
  is 
  wider 
  than 
  

   long; 
  the 
  third 
  longer 
  than 
  wide. 
  The 
  intergular 
  scutum 
  is 
  subtrigonal, 
  the 
  apex 
  shortened 
  by 
  short 
  facets, 
  and 
  ex- 
  

   tending 
  three-fourths 
  the 
  distance 
  to 
  the 
  posterior 
  margin 
  of 
  the 
  bone. 
  

  

  This 
  species 
  was 
  discovered 
  by 
  my 
  friend, 
  Dr. 
  Samuel 
  Lockwood, 
  who 
  lent 
  the 
  single 
  

   and 
  typical 
  specimen 
  from 
  his 
  private 
  collection 
  for 
  description. 
  It 
  is 
  dedicated 
  to 
  Prof. 
  

   J. 
  P. 
  Lesley, 
  the 
  Geologist, 
  and 
  Secretary 
  of 
  the 
  American 
  Philosophical 
  Society. 
  

  

  