﻿TADPOLES. 
  

  

  99 
  

  

  XIII. 
  Tadpoles. 
  

  

  The 
  term 
  tadpole 
  is 
  restricted 
  to 
  the 
  developmental 
  

   stages 
  between 
  the 
  formation 
  of 
  the 
  spiraculum 
  and 
  

   the 
  egress 
  of 
  the 
  fore 
  limbs, 
  and 
  corresponds 
  to 
  the 
  

   second 
  and 
  third 
  periods 
  of 
  Duges. 
  Descriptions 
  are 
  

   preferably 
  drawn 
  up 
  from 
  specimens 
  in 
  the 
  third 
  

   period, 
  which 
  begins 
  with 
  the 
  budding 
  of 
  the 
  hind 
  

   limbs. 
  

  

  Form. 
  — 
  The 
  head 
  and 
  body 
  are 
  so 
  fused 
  that 
  it 
  is 
  

  

  B 
  

  

  Open 
  mouth 
  of 
  — 
  A. 
  Pelodytes 
  piuictatus. 
  b. 
  Alytes 
  ohstetricans. 
  

   h.o. 
  Buccal 
  orifice, 
  l.p. 
  Labial 
  papillae, 
  m. 
  Mandibles, 
  t. 
  

   Series 
  of 
  labial 
  teeth. 
  (From 
  ' 
  P. 
  Z. 
  S.,' 
  1891.) 
  

  

  