﻿80 
  INTRODUCTION. 
  

  

  envelops 
  with 
  external 
  gills 
  or 
  just 
  before 
  

   their 
  appearance, 
  with 
  the 
  tail 
  more 
  or 
  less 
  

   developed. 
  

   Yitellus 
  1 
  — 
  1^ 
  millimetres 
  in 
  diameter, 
  black 
  

  

  above 
  Discoglossus. 
  

  

  Vitellus 
  2 
  millimetres 
  in 
  diameter, 
  brown 
  above. 
  

  

  Bomhinator. 
  

   B. 
  Irregularly 
  disposed 
  in 
  a 
  thick 
  mucilaginous 
  

   band 
  (formed 
  by 
  fusion 
  in 
  the 
  cloaca 
  of 
  the 
  

   contents 
  of 
  the 
  two 
  oviducts) 
  ; 
  vitellus 
  dark 
  

   brown 
  or 
  black, 
  with 
  the 
  lower 
  pole 
  white, 
  

   I2 
  — 
  2^ 
  millimetres 
  in 
  diameter, 
  the 
  embryo 
  

   leaving 
  the 
  envelops 
  before 
  the 
  appearance 
  

   of 
  the 
  external 
  gills 
  and 
  tailless. 
  

  

  Peloclytes, 
  Pelohates. 
  

   c. 
  In 
  regular 
  files 
  in 
  two 
  long 
  mucilaginous 
  

   strings 
  ; 
  vitellus 
  entirely 
  dark 
  brown 
  or 
  

   black, 
  or 
  with 
  a 
  whitish 
  lower 
  pole, 
  the 
  

   embryo 
  leaving 
  the 
  envelops 
  before 
  the 
  

   appearance 
  of 
  the 
  external 
  gills 
  and 
  with 
  a 
  

  

  rudimentary 
  tail 
  Biifo. 
  

  

  Yitellus 
  1\ 
  — 
  2 
  millimetres 
  in 
  diameter; 
  eggs, 
  in 
  

   each 
  string, 
  in 
  three 
  or 
  four 
  files 
  when 
  floating, 
  

  

  in 
  two 
  when 
  stretched 
  B. 
  vulgaris. 
  

  

  Yitellus 
  1 
  — 
  1^ 
  millimetres 
  in 
  diameter; 
  eggs 
  in 
  

   three 
  or 
  four 
  files 
  when 
  floating, 
  in 
  two 
  when 
  

  

  stretched 
  B. 
  viridis. 
  

  

  Yitellus 
  1 
  — 
  1^ 
  millimetres 
  in 
  diameter, 
  with 
  

  

  whitish 
  lower 
  pole 
  ; 
  eggs 
  in 
  two 
  files 
  when 
  

  

  floating, 
  in 
  one 
  when 
  stretched 
  . 
  B. 
  calamita. 
  

  

  D. 
  In 
  large 
  lumps 
  ; 
  upper 
  pole 
  brown 
  or 
  black, 
  

  

  lower 
  whitish 
  or 
  yellowish 
  ; 
  the 
  embryo 
  

  

  leaving 
  the 
  envelops 
  with 
  external 
  gills 
  and 
  

  

  a 
  well-developed 
  tail. 
  

  

  1. 
  Envelop, 
  when 
  fully 
  swollen 
  out, 
  measuring 
  

  

  3 
  — 
  4 
  millimetres 
  in 
  diameter; 
  vitellus 
  

  

  yellowish 
  white 
  with 
  brown 
  upper 
  pole, 
  1^ 
  

  

  millimetres 
  in 
  diameter; 
  embryo 
  yellowish. 
  

  

  Hi/Ia. 
  

  

  