﻿378 
  BABCOCK: 
  NEW 
  ENGLAND 
  TURTLES. 
  

  

  Graptemys 
  geographica 
  (Le 
  Sueur). 
  

  

  Geographical 
  Terrapin; 
  Map 
  Turtle. 
  

  

  Plate 
  25. 
  

  

  Tcstudo 
  geographica 
  Le 
  Sueiir, 
  Joiirn. 
  Acad. 
  Nat. 
  Sci. 
  Phila., 
  1817, 
  vol. 
  1, 
  p. 
  86, 
  pi. 
  5. 
  

   Graptemys 
  geographica 
  Agassiz, 
  Contrib. 
  Nat. 
  Hist. 
  U. 
  S., 
  1857, 
  vol. 
  1, 
  p. 
  436. 
  

  

  Size. 
  — 
  Adult 
  individuals 
  average 
  twelve 
  inches 
  in 
  length. 
  Ditmars 
  (1907, 
  p. 
  44) 
  gives 
  

   the 
  following 
  dimensions 
  of 
  a 
  female: 
  total 
  length 
  of 
  carapace, 
  9| 
  inches; 
  width 
  of 
  carapace, 
  

   7i; 
  length 
  of 
  plastron, 
  8; 
  width, 
  flat 
  portion 
  of 
  plastron, 
  4; 
  width 
  of 
  head, 
  l|. 
  Females 
  

   attain 
  a 
  greater 
  size 
  than 
  males. 
  

  

  Color. 
  — 
  The 
  carapace 
  is 
  dull 
  olive 
  or 
  brown, 
  sometimes 
  mottled 
  and 
  covered 
  \\ith 
  an 
  

   irregular 
  reticulation 
  of 
  thin 
  greenish 
  or 
  yellow 
  Unes, 
  often 
  indistinct. 
  The 
  under 
  side 
  of 
  

   the 
  marginals 
  is 
  yellow 
  mth 
  a 
  central 
  blotch. 
  The 
  plastron 
  is 
  yellow 
  with 
  a 
  pinkish 
  tinge 
  

   and 
  a 
  faint 
  greenish 
  mark 
  across 
  each 
  half. 
  The 
  head 
  and 
  neck 
  are 
  striped 
  with 
  narrow 
  

   yellow 
  Unes. 
  There 
  is 
  an 
  irregular 
  yellow 
  spot 
  behind 
  each 
  ear. 
  The 
  tail 
  is 
  also 
  striped 
  

   with 
  yellow. 
  

  

  Description. 
  — 
  The 
  characteristics 
  of 
  this 
  species 
  are: 
  a 
  strong 
  blunt 
  keel 
  running 
  through 
  

   the 
  vertebral 
  shields 
  of 
  the 
  carapace, 
  which 
  is 
  rather 
  flat 
  and 
  flaring 
  behind, 
  mth 
  a 
  somewhat 
  

   denticulate 
  edge; 
  the 
  great 
  mdth 
  of 
  the 
  smooth 
  and 
  flat 
  horizontal 
  alveolar 
  surfaces 
  in 
  the 
  

   jaws, 
  and 
  the 
  "spoon-shaped 
  dilatation 
  of 
  the 
  extremity 
  of 
  the 
  lower 
  jaw"; 
  the 
  absence 
  of 
  a 
  

   notch 
  in 
  the 
  upper 
  jaw; 
  and 
  the 
  presence 
  of 
  large 
  scales 
  on 
  the 
  feet. 
  The 
  toes 
  are 
  short. 
  The 
  

   tail 
  is 
  longer 
  in 
  males 
  than 
  in 
  females. 
  The 
  carapace 
  of 
  the 
  young 
  is 
  strongly 
  keeled 
  and 
  deeply 
  

   notched 
  laterally 
  and 
  posteriorly. 
  

  

  Geographic 
  Distribution. 
  — 
  The 
  home 
  of 
  this 
  species 
  is 
  the 
  Mississippi 
  Valley, 
  ranging 
  

   north 
  through 
  Pennsylvania 
  and 
  New 
  York 
  to 
  Lake 
  Champlain, 
  and 
  south 
  to 
  Oklahoma 
  and 
  

   northwestern 
  Texas. 
  

  

  New 
  England 
  Records. 
  — 
  Thompson 
  (1842, 
  1853) 
  reports 
  the 
  Geographical 
  Terrapin 
  from 
  

   Colchester, 
  Vermont, 
  near 
  the 
  mouth 
  of 
  the 
  Winooski 
  River. 
  He 
  says 
  it 
  is 
  "quite 
  common 
  all 
  

   along 
  the 
  eastern 
  shore 
  of 
  Lake 
  Champlain." 
  It 
  has 
  not 
  been 
  reported 
  elsewhere 
  in 
  New 
  

   England. 
  There 
  are 
  no 
  specimens 
  of 
  this 
  species 
  in 
  the 
  Society's 
  collection. 
  

  

  Habitat. 
  — 
  This 
  species 
  is 
  considered 
  more 
  a 
  river 
  than 
  a 
  pond 
  terrapin. 
  

  

  Numbers. 
  — 
  Throughout 
  the 
  central 
  portion 
  of 
  its 
  range, 
  it 
  is 
  very 
  abundant. 
  

  

  Breeding 
  Habits. 
  — 
  Thompson 
  (1853, 
  p. 
  29) 
  writes 
  as 
  follows 
  regarding 
  a 
  specimen 
  which 
  

   he 
  caught: 
  "It 
  was 
  a 
  female, 
  containing 
  14 
  mature 
  eggs 
  in 
  the 
  oviduct, 
  with 
  about 
  the 
  same 
  

  

  