﻿284 
  ANNUAL 
  EEPORT 
  SMITHSONIAN 
  INSTITUTION, 
  192 
  9 
  

  

  come 
  of 
  very 
  little 
  use, 
  and 
  the 
  energy 
  that 
  is 
  used 
  by 
  other 
  animals 
  

   in 
  the 
  specialization 
  of 
  bodily 
  parts 
  is 
  in 
  parasites 
  freed 
  and 
  given 
  over 
  

   to 
  reproduction, 
  resulting 
  in 
  the 
  preservation 
  of 
  the 
  race. 
  Conse- 
  

   quently 
  the 
  genital 
  organs 
  of 
  parasites 
  are 
  greatly 
  enlarged, 
  and 
  all 
  

   parasites 
  are 
  very 
  prolific. 
  

  

  CONCLUSIONS 
  

  

  Owing 
  to 
  extinction, 
  the 
  normal 
  course 
  of 
  evolution 
  has 
  been 
  inter- 
  

   rupted 
  innumerable 
  times. 
  There 
  is 
  no 
  line 
  of 
  evolution 
  to 
  which 
  

   this 
  statement 
  would 
  not 
  apply. 
  Races 
  have 
  been 
  preserved 
  not 
  by 
  

   means 
  of 
  their 
  most 
  brilliant 
  representatives, 
  for 
  great 
  achievements 
  

   cause 
  some 
  deficiency 
  of 
  vital 
  racial 
  force, 
  but 
  rather 
  through 
  mediocre 
  

   individuals. 
  We 
  are 
  even 
  able 
  to 
  establish 
  an 
  empiric 
  law 
  that 
  

   "the 
  upwelling 
  of 
  future 
  organic 
  rulers 
  begins 
  in 
  unobtrusive 
  small 
  

   forms," 
  ^^ 
  or, 
  as 
  expressed 
  by 
  Cope, 
  in 
  the 
  "survival 
  of 
  the 
  unspecial- 
  

   ized," 
  because, 
  as 
  he 
  states, 
  the 
  highly 
  developed 
  or 
  greatly 
  special- 
  

   ized 
  types 
  of 
  one 
  geologic 
  period 
  are 
  not 
  the 
  parents 
  of 
  the 
  types 
  of 
  

   succeeding 
  periods.^^ 
  

  

  Especially 
  important 
  and 
  interesting 
  in 
  this 
  respect 
  are 
  those 
  per- 
  

   sistent 
  types 
  that 
  have 
  gone 
  through 
  a 
  number 
  of 
  geological 
  periods 
  

   without 
  great 
  alterations 
  in 
  structure. 
  Their 
  evolution 
  has 
  been 
  

   arrested,^^ 
  and 
  in 
  recompense 
  they 
  have 
  received 
  a 
  longevity 
  that 
  

   seems 
  to 
  approach 
  immortalit3\ 
  

  

  36 
  Charles 
  Schuchert, 
  Historical 
  geology, 
  p. 
  449. 
  

   «' 
  Idem, 
  p. 
  450. 
  

  

  3S 
  Rudolph 
  Ruedemann, 
  Paleontology 
  of 
  arrested 
  evolution. 
  New 
  York 
  State 
  Museum 
  Bulletin, 
  

   No. 
  19G, 
  pp. 
  107-134, 
  1918. 
  

  

  