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  ANNUAL 
  REPORT 
  SMITHSONIAN 
  INSTITUTION, 
  1929 
  

  

  says: 
  "In 
  the 
  potato, 
  as 
  tuber 
  production 
  has 
  increased, 
  seed 
  pro- 
  

   duction 
  has 
  decreased. 
  Now 
  potatoes 
  do 
  not 
  produce 
  bolls 
  as 
  freely 
  

   as 
  they 
  did 
  years 
  ago." 
  ^^ 
  So-called 
  seedless 
  fruits 
  belong 
  to 
  the 
  same 
  

   category. 
  Some 
  of 
  these 
  highly 
  specialized 
  plants, 
  if 
  left 
  without 
  the 
  

   attention 
  of 
  a 
  gardener, 
  would 
  perhaps 
  restore 
  their 
  lost 
  power 
  of 
  

   producing 
  seed, 
  and 
  they 
  would 
  at 
  the 
  same 
  time 
  lose 
  their 
  acquired 
  

   artificial 
  qualities; 
  but 
  most 
  of 
  them 
  would 
  soon 
  become 
  extinct, 
  if 
  it 
  

   were 
  not 
  for 
  the 
  intervention 
  of 
  man. 
  

  

  OBSERVATIONS 
  ON 
  PLANTS 
  APPLIED 
  TO 
  ANIMALS 
  

  

  The 
  observation 
  of 
  highly 
  specialized 
  plants 
  helps 
  us 
  to 
  explain 
  

   tentatively 
  the 
  alterations 
  that 
  are 
  going 
  on 
  in 
  highlj^ 
  specialized 
  

   animals 
  and 
  that 
  decrease 
  their 
  productivity. 
  The 
  parts 
  affected 
  are 
  

   the 
  genital 
  organs, 
  or, 
  to 
  speak 
  more 
  correctly, 
  perhaps, 
  the 
  genital 
  

   glands, 
  the 
  secretions 
  of 
  which 
  may 
  more 
  or 
  less 
  decrease 
  or 
  cease 
  

   entirely, 
  like 
  the 
  production 
  of 
  seed 
  ceases 
  in 
  highly 
  specialized 
  plants. 
  

   Animals 
  as 
  individuals 
  would 
  not 
  be 
  harmed 
  by 
  this 
  loss; 
  they 
  might 
  

   even 
  be 
  benefited 
  by 
  the 
  transfer 
  of 
  energy 
  to 
  other 
  parts 
  of 
  the 
  body, 
  

   but 
  for 
  the 
  preservation 
  of 
  a 
  race 
  the 
  loss 
  would 
  be 
  fatal. 
  On 
  the 
  

   other 
  hand, 
  the 
  specialization 
  of 
  certain 
  parts 
  of 
  the 
  animal 
  body 
  to 
  

   form 
  reproductive 
  or 
  genital 
  organs 
  diminishes 
  prolification. 
  In 
  the 
  

   lower 
  organisms 
  reproduction 
  goes 
  on 
  by 
  the 
  fission 
  of 
  the 
  whole 
  

   body. 
  In 
  the 
  Infusoria 
  such 
  fission 
  may 
  even 
  be 
  produced 
  mechan- 
  

   ically 
  by 
  skillful 
  dissection. 
  But 
  the 
  evolution 
  of 
  the 
  animal 
  king- 
  

   dom 
  is 
  paralleled 
  by 
  a 
  decrease 
  in 
  prolification. 
  Most 
  of 
  the 
  mem- 
  

   bers 
  of 
  a 
  colony 
  of 
  Coelenterata 
  may 
  lose 
  entirely 
  the 
  power 
  of 
  repro- 
  

   duction, 
  which 
  has 
  become 
  a 
  function 
  of 
  certain 
  specialized 
  individ- 
  

   uals. 
  In 
  other 
  animals 
  reproduction 
  through 
  fission 
  occurs 
  only 
  by 
  

   budding 
  in 
  certain 
  parts 
  of 
  the 
  body. 
  The 
  origin 
  of 
  the 
  genital 
  

   glands 
  of 
  the 
  higher 
  animals 
  may 
  be 
  traced 
  to 
  budding, 
  but 
  in 
  greatly 
  

   modified 
  and 
  highly 
  specialized 
  form, 
  a 
  form 
  that 
  is 
  easily 
  subject 
  to 
  

   the 
  influence 
  of 
  many 
  exterior 
  and 
  interior 
  agencies. 
  All 
  the 
  varia- 
  

   tions 
  in 
  the 
  reproduction 
  of 
  different 
  animals 
  and 
  in 
  their 
  fertility 
  

   must 
  be 
  considered 
  in 
  connection 
  with 
  the 
  structure, 
  function, 
  and 
  

   alteration 
  of 
  these 
  important 
  parts 
  of 
  every 
  animal 
  that 
  has 
  a 
  some- 
  

   what 
  high 
  systematic 
  position. 
  

  

  By 
  all 
  these 
  considerations 
  we 
  are 
  able 
  not 
  only 
  to 
  explain 
  extinc- 
  

   tion 
  brought 
  about 
  by 
  the 
  great 
  specialization 
  and 
  accompanying 
  

   sterility 
  of 
  organisms, 
  but 
  to 
  understand 
  the 
  origin 
  of 
  those 
  peculiar 
  

   structures 
  that 
  paleontologists 
  consider 
  indications 
  of 
  the 
  old 
  age 
  of 
  

   a 
  race. 
  Some 
  kinds 
  of 
  specialization 
  that 
  affect 
  the 
  reproductive 
  

   powers 
  of 
  a 
  race 
  may 
  not 
  cause 
  immediate 
  sterility, 
  but 
  may 
  produce 
  

  

  " 
  L. 
  H. 
  Bailey, 
  Plant-breeding, 
  p. 
  225. 
  The 
  writer 
  feels 
  greatly 
  indebted 
  to 
  Dr. 
  0. 
  E. 
  Jennings 
  for 
  all 
  

   the 
  information 
  concerning 
  cultivated 
  plants. 
  

  

  