﻿SPINY 
  SOFT-SHELLED 
  TURTLE. 
  421 
  

  

  doubtless 
  originally 
  a 
  western 
  species, 
  and 
  never 
  migrating 
  by 
  land, 
  can 
  have 
  passed 
  by 
  water 
  

   from 
  the 
  Great 
  Valley 
  of 
  the 
  Mississippi 
  to 
  the 
  northern 
  lakes, 
  and 
  to 
  the 
  Mohawk 
  and 
  even 
  

   Hudson 
  river. 
  At 
  the 
  som'ce 
  of 
  St. 
  Peter's 
  river 
  in 
  times 
  of 
  flood 
  there 
  is 
  a 
  free 
  conmiunication 
  

   with 
  Red 
  river 
  of 
  Lake 
  Winnipeg, 
  (lat. 
  48°, 
  Say, 
  in 
  Long's 
  Exp. 
  ;) 
  which 
  thus 
  affords 
  a 
  passage 
  

   for 
  the 
  Trionyx 
  ferox 
  to 
  the 
  Lake 
  of 
  the 
  Woods. 
  Again, 
  the 
  Upper 
  IlUnois 
  is 
  well 
  known 
  to 
  

   communicate 
  with 
  the 
  waters 
  of 
  Lake 
  Michigan 
  in 
  spring 
  floods, 
  so 
  that 
  even 
  loaded 
  boats 
  

   may 
  pass; 
  and 
  in 
  this 
  way 
  does 
  om* 
  animal 
  reach 
  the 
  chain 
  of 
  lakes, 
  that 
  open 
  into 
  the 
  St. 
  

   Lawrence 
  river. 
  Lastly, 
  previous 
  to 
  the 
  construction 
  of 
  the 
  New 
  York 
  Canal, 
  Wood 
  creek, 
  

   at 
  the 
  head 
  of 
  the 
  Mohawk, 
  also 
  at 
  'spring 
  floods' 
  communicated 
  with 
  the 
  waters 
  of 
  the 
  Oswego 
  

   river; 
  and 
  consequently 
  there 
  the 
  Trionyx 
  could 
  pass 
  to 
  and 
  become 
  'common 
  in 
  the 
  Mohawk,' 
  

   and 
  reach 
  the 
  Hudson, 
  though 
  absent 
  from 
  every 
  other 
  river 
  opening 
  into 
  the 
  Atlantic, 
  be- 
  

   tween 
  the 
  St. 
  LawTence 
  on 
  the 
  one 
  hand, 
  and 
  the 
  Savannah 
  river 
  on 
  the 
  other." 
  

  

  The 
  connection 
  of 
  the 
  Champlain 
  Valley 
  and 
  the 
  St. 
  Lawrence 
  basin 
  probably 
  accounts 
  

   for 
  the 
  occurrence 
  in 
  Lake 
  Champlain. 
  

  

  Habitat. 
  — 
  Soft 
  muddy 
  bottoms 
  of 
  rivers 
  and 
  ponds, 
  usually 
  in 
  shallow 
  water. 
  

  

  Numbers. 
  — 
  In 
  the 
  central 
  portion 
  of 
  its 
  range, 
  this 
  turtle 
  is 
  abundant. 
  

  

  Breeding 
  Habits. 
  — 
  The 
  eggs 
  are 
  deposited 
  during 
  June 
  in 
  sandy 
  soil 
  not 
  far 
  from 
  the 
  water, 
  

   the 
  female 
  sometimes 
  burjdng 
  herself 
  almost 
  completely 
  dming 
  the 
  process. 
  The 
  process 
  of 
  

   laying 
  the 
  eggs 
  has 
  been 
  observed 
  to 
  require 
  in 
  certain 
  instances 
  several 
  days 
  for 
  its 
  com- 
  

   pletion. 
  Several 
  dozen 
  round, 
  white, 
  brittle, 
  thin-shelled 
  eggs 
  are 
  deposited, 
  averaging 
  sUghtly 
  

   over 
  one 
  inch 
  in 
  diameter. 
  Mitsukuri 
  (1905, 
  p. 
  263) 
  gives 
  an 
  interesting 
  account 
  of 
  the 
  breed- 
  

   ing 
  habits 
  of 
  an 
  alhed 
  species, 
  Amyda 
  japonica. 
  He 
  says: 
  "The 
  process 
  of 
  egg 
  deposition 
  

   is 
  very 
  interesting. 
  A 
  female 
  comes 
  out 
  of 
  the 
  water 
  and 
  wanders 
  about 
  a 
  httle 
  while 
  on 
  the 
  

   banks 
  of 
  the 
  pond 
  in 
  search 
  of 
  a 
  suitable 
  locahty 
  in 
  which 
  to 
  deposit 
  eggs. 
  Having 
  finally 
  

   chosen 
  a 
  spot, 
  with 
  her 
  head 
  directed 
  up 
  the 
  bank 
  she 
  firmly 
  implants 
  her 
  outstretched 
  fore 
  

   feet 
  on 
  the 
  earth, 
  and 
  diu-ing 
  the 
  whole 
  operation 
  never 
  moves 
  these. 
  The 
  process 
  of 
  egg 
  

   deposition, 
  which 
  takes 
  altogether 
  about 
  twenty 
  minutes, 
  may 
  be 
  divided 
  into 
  'three 
  portions 
  

   occupying 
  about 
  the 
  same 
  length 
  of 
  time, 
  namely: 
  (1) 
  digging 
  a 
  hole, 
  (2) 
  di'opping 
  eggs 
  in 
  it, 
  

   and 
  (3) 
  closing 
  the 
  hole. 
  The 
  digging 
  of 
  the 
  hole 
  is 
  done 
  entirely 
  with 
  the 
  hind 
  legs. 
  Each 
  

   with 
  its 
  nails 
  outstretched 
  is 
  moved 
  firmly 
  from 
  side 
  to 
  side 
  — 
  that 
  is, 
  the 
  right 
  foot 
  from 
  

   right 
  to 
  left 
  and 
  the 
  left 
  from 
  left 
  to 
  right, 
  and 
  the 
  two 
  are 
  worked 
  in 
  a 
  regular 
  alternation, 
  

   while 
  the 
  body 
  is 
  swayed 
  a 
  httle 
  from 
  side 
  to 
  side, 
  accompanying 
  the 
  motion 
  of 
  the 
  legs. 
  The 
  

   force 
  put 
  in 
  the 
  lateral 
  pressure 
  of 
  the 
  feet 
  is 
  so 
  strong 
  that 
  the 
  earth 
  that 
  has 
  been 
  dug 
  out 
  is 
  

   sometunes 
  thi-own 
  off 
  to 
  a 
  distance 
  of 
  10 
  feet 
  or 
  more, 
  although 
  the 
  largest 
  part 
  of 
  it 
  is 
  heaped 
  

   up 
  around 
  the 
  hole. 
  Digging 
  seems 
  to 
  be 
  continued 
  as 
  long 
  as 
  there 
  is 
  any 
  earth 
  within 
  the 
  

   reach 
  of 
  the 
  legs 
  to 
  be 
  brought 
  up. 
  The 
  result 
  is 
  a 
  squarish 
  hole 
  mth 
  the 
  angles 
  rounded 
  off, 
  

   and 
  although 
  its 
  size 
  differs 
  with 
  the 
  size 
  of 
  the 
  female, 
  it 
  is 
  generally 
  about 
  3 
  to 
  4 
  inches 
  across 
  

  

  