﻿44 
  

  

  INTEODUCTION. 
  

  

  segment 
  to 
  the 
  limb, 
  a 
  sort 
  of 
  cms 
  secondarium. 
  Tkis 
  

   is 
  especially 
  striking 
  in 
  Pelodjjtes, 
  where 
  the 
  two 
  

   bones 
  fuse, 
  and 
  resemble, 
  but 
  in 
  length, 
  the 
  crus 
  or 
  

   tibia-fibula. 
  

  

  In 
  the 
  Bufonidde, 
  Hylidde, 
  and 
  Banidde 
  a 
  calcified 
  

   epiphysis 
  unites 
  the 
  two 
  bones 
  at 
  either 
  extremity. 
  

   InBana 
  SindBufo 
  a 
  small 
  sesamoid 
  bone 
  is 
  present 
  on 
  

   the 
  inner 
  side 
  of 
  the 
  proximal 
  extremity 
  of 
  the 
  tarsus. 
  

   A 
  series 
  of 
  three 
  or 
  four 
  small 
  distal 
  tarsals 
  (Fig. 
  19) 
  

   intervenes 
  between 
  the 
  astragalus 
  and 
  calcaneum 
  and 
  

   the 
  three 
  inner 
  metatarsals, 
  whilst 
  the 
  two 
  outer 
  meta- 
  

   tarsals 
  are 
  directly 
  in 
  contact 
  with 
  the 
  calcaneum. 
  

   The 
  toes 
  are 
  five 
  in 
  number, 
  with 
  elongate 
  meta- 
  

   tarsals 
  and 
  2, 
  2, 
  3, 
  4, 
  3 
  phalanges. 
  A 
  rudimentary 
  

   inner 
  digit, 
  the 
  so-called 
  pr^hallux, 
  consists 
  of 
  a 
  

  

  Fig. 
  19, 
  

  

  Tarsus 
  

  

  c 
  

  

  A 
  JtJ 
  <J 
  

  

  of 
  — 
  A. 
  Bombinator 
  pachypus. 
  b. 
  Pelodytes 
  punctatus. 
  

   G. 
  Rana 
  temporaria. 
  

  

  metatarsal 
  and 
  one 
  or 
  two 
  phalanges, 
  the 
  development 
  

   of 
  which 
  corresponds 
  with 
  that 
  of 
  the 
  inner 
  meta- 
  

   tarsal 
  tubercle. 
  In 
  Bombinator, 
  Ahjtes, 
  and 
  Pelodijtes 
  

   the 
  distal 
  tarsals 
  as 
  well 
  as 
  the 
  prsehallux 
  remain 
  

   cartilaginous 
  throughout 
  life; 
  in 
  Discoglossus 
  the 
  

   prsehallux 
  ossifies, 
  but 
  the 
  distal 
  tarsals 
  remain 
  cartila- 
  

   ginous. 
  

  

  The 
  following 
  is 
  a 
  Synopsis 
  of 
  the 
  Genera 
  and 
  

   Species, 
  based 
  on 
  the 
  osteological 
  characters 
  : 
  

  

  I. 
  Prsecoracoid 
  curved, 
  connected 
  with 
  the 
  coracoid 
  

   by 
  an 
  arched 
  (epicoracoid) 
  cartilage 
  over- 
  

   lapping 
  its 
  fellow 
  (Arcifera). 
  

  

  