﻿INTEGUMENT. 
  29 
  

  

  Museum. 
  These 
  albinos 
  are 
  of 
  a 
  uniform 
  yellowish 
  

   flesh-colour, 
  with 
  silvery 
  or 
  golden 
  iris 
  and 
  cherry-red 
  

   pupil 
  ; 
  the 
  yellow 
  ventral 
  blotches 
  are 
  preserved 
  in 
  

   Bomhinator. 
  A 
  figure 
  of 
  a 
  young 
  Alytes 
  albino 
  reared 
  

   by 
  Lataste 
  is 
  given 
  on 
  Plate 
  YII. 
  Albino 
  specimens 
  

   oi 
  Alytes 
  ohstetricans 
  obtained 
  from 
  tadpoles 
  by 
  Heron- 
  

   Royer 
  paired 
  in 
  confinement, 
  and 
  produced 
  offspring 
  

   that 
  were 
  likewise 
  affected 
  with 
  complete 
  albinism. 
  

   But 
  for 
  the 
  difficulty 
  in 
  getting 
  these 
  Batrachians 
  to 
  

   breed 
  in 
  captivity, 
  a 
  race 
  of 
  albinos 
  could 
  no 
  doubt 
  be 
  

   fixed 
  by 
  artificial 
  selection, 
  as 
  in 
  the 
  case 
  of 
  the 
  

   axolotl, 
  the 
  numerous 
  "white" 
  examples 
  of 
  which 
  

   are 
  said 
  to 
  be 
  all 
  descended 
  from 
  an 
  albino 
  male 
  

   which 
  paired 
  with 
  normal 
  females 
  in 
  the 
  Jardin 
  des 
  

   Plantes 
  at 
  Paris 
  some 
  thirty 
  years 
  ago. 
  

  

  Batrachians 
  often 
  ''change 
  skin," 
  — 
  -about 
  once 
  a 
  

   month 
  during 
  the 
  spring 
  and 
  summer. 
  The 
  thin, 
  trans- 
  

   parent 
  outer 
  layer 
  of 
  the 
  epidermis 
  becomes 
  detached, 
  

   about 
  the 
  mouth, 
  and, 
  lubricated 
  by 
  an 
  abundant 
  secre- 
  

   tion 
  of 
  the 
  slime 
  glands, 
  is 
  pulled 
  off 
  by 
  movements 
  

   of 
  both 
  fore 
  and 
  hind 
  limbs, 
  often 
  in 
  a 
  single 
  piece 
  

   turned 
  inside 
  out, 
  especially 
  when 
  the 
  operation 
  is 
  

   performed 
  in 
  the 
  water, 
  and 
  finally 
  swallowed 
  by 
  its 
  

   owner. 
  The 
  casting 
  of 
  the 
  epidermis 
  on 
  land 
  is 
  a 
  

   slower 
  process, 
  accompanied 
  by 
  ludicrous 
  contortions 
  ; 
  

   in 
  the 
  common 
  toad 
  it 
  may 
  last 
  nearly 
  an 
  hour. 
  

  

  Fig. 
  10. 
  

  

  

  

  Piece 
  of 
  dorsal 
  integument 
  of 
  male 
  Bomhinator 
  jpachypus 
  ( 
  X 
  8), 
  

   showing 
  warts 
  and 
  epidermal 
  horny 
  asperities. 
  

  

  