﻿akt.19 
  CONCERNING 
  BIRDS 
  ' 
  TONGUES 
  GARDNER 
  3 
  

  

  CARPODACUS 
  MEXICANUS 
  FRONTALIS 
  

  

  The 
  section 
  is 
  cordiform 
  in 
  shape. 
  The 
  ventral 
  and 
  lateral 
  sur- 
  

   faces 
  are 
  covered 
  with 
  thin 
  cornified 
  epithelium. 
  The 
  dorsal 
  sur- 
  

   face 
  is 
  composed 
  of 
  a 
  thick 
  knoblike 
  mass 
  of 
  stratified 
  squamous 
  

   epithelium 
  through 
  which 
  no 
  glandular 
  ducts 
  were 
  seen 
  to 
  pass. 
  

   Several 
  large 
  nerve 
  trunks 
  pass 
  through 
  the 
  length 
  of 
  the 
  tongue 
  

   beneath 
  the 
  branches 
  of 
  the 
  ceratohyals. 
  Nerve 
  corpuscles 
  are 
  

   found 
  in 
  the 
  posterior 
  end 
  of 
  the 
  tongue. 
  

  

  It 
  is 
  apparent 
  even 
  from 
  such 
  a 
  brief 
  survey 
  that 
  the 
  tongue 
  must 
  

   serve, 
  in 
  part 
  in 
  some 
  species 
  at 
  least, 
  as 
  an 
  accessory 
  salivary 
  gland. 
  

   In 
  addition 
  tactile 
  sense 
  must 
  be 
  ascribed 
  to 
  it, 
  if 
  not 
  even 
  that 
  of 
  

   taste, 
  as 
  Botezat 
  2 
  suggests. 
  

  

  The 
  variations 
  found 
  in 
  bird 
  tongues 
  are 
  very 
  extensive 
  and 
  often 
  

   complex. 
  

  

  Embryological 
  study 
  shows 
  that 
  this 
  organ 
  in 
  birds 
  is 
  primitively 
  

   a 
  paired 
  structure 
  arising 
  from 
  the 
  second 
  and 
  third 
  visceral 
  arches. 
  

   This 
  paired 
  condition 
  reflects 
  itself 
  in 
  the 
  hyoid 
  bones, 
  the 
  two 
  fore- 
  

   most 
  of 
  which, 
  the 
  ceratohyals, 
  being 
  typically 
  unfused 
  and 
  em- 
  

   bedded 
  in 
  the 
  flesh 
  of 
  the 
  tongue 
  itself. 
  Posterior 
  to 
  this 
  paired 
  

   position 
  is 
  a 
  median 
  unpaired 
  tract, 
  the 
  basihyal. 
  Upon 
  this 
  

   foundation 
  are 
  constructed 
  all 
  the 
  elaborate 
  variations 
  to 
  be 
  found 
  

   among 
  the 
  tongues 
  of 
  birds. 
  Thus 
  the 
  tongues 
  of 
  woodpeckers, 
  

   which 
  at 
  first 
  sight 
  seem 
  to 
  be 
  constructed 
  on 
  a 
  wholly 
  different 
  pat- 
  

   tern 
  than 
  that 
  of 
  a 
  robin, 
  are, 
  on 
  last 
  analysis, 
  seen 
  to 
  be 
  but 
  an 
  

   extensive 
  modification 
  of 
  this 
  rather 
  primitive 
  type, 
  the 
  ceratohyals 
  

   being 
  fused 
  to 
  a 
  small 
  spearlike 
  tip 
  and 
  the 
  basihyal 
  greatly 
  elon- 
  

   gated. 
  This 
  is 
  represented 
  superficially 
  by 
  the 
  small 
  barbed 
  sharp 
  

   tip, 
  the 
  true 
  tongue, 
  while 
  behind 
  this 
  is 
  the 
  fleshy 
  cylindrical 
  

   extensive 
  basihyal 
  portion 
  often 
  spoken 
  of 
  as 
  the 
  tongue. 
  

  

  As 
  Lucas 
  3 
  pointed 
  out 
  in 
  his 
  work, 
  the 
  tongue 
  of 
  a 
  robin 
  (fig. 
  1) 
  

   serves 
  as 
  a 
  ground 
  pattern 
  for 
  many 
  modifications. 
  In 
  this 
  bird 
  it 
  

   is 
  a 
  slender, 
  horny, 
  lanceolate 
  organ, 
  wider 
  and 
  fleshier 
  at 
  the 
  base 
  

   than 
  the 
  tip 
  and 
  narrowing 
  to 
  the 
  tip, 
  which 
  is 
  translucent, 
  corni- 
  

   fied, 
  somewhat 
  split 
  and 
  frayed, 
  with 
  a 
  tendency 
  to 
  curl. 
  

  

  Posteriorly 
  the 
  tongue 
  ends 
  in 
  a 
  free 
  edge 
  which 
  is 
  deeply 
  con- 
  

   cave, 
  with 
  the 
  concavity 
  looking 
  caudad 
  and 
  armed 
  with 
  many 
  sharp 
  

   conical 
  spines 
  which 
  are 
  firm 
  in 
  texture 
  but 
  bend 
  readily. 
  Laterally, 
  

  

  2 
  Botezat, 
  E. 
  Die 
  sensiblen 
  Nervenendapparate 
  in 
  den 
  Plornpapillen 
  der 
  Vogel 
  in 
  

   Zusammenhang 
  mit 
  Studien 
  zur 
  vergleichenden 
  Morphologie 
  und 
  Physiologie 
  der 
  Sinnes- 
  

   organe, 
  Anat. 
  Anz., 
  vol. 
  34, 
  1908. 
  

  

  Botezat, 
  E. 
  Die 
  sensiblen 
  Nervenendapparate 
  und 
  die 
  Gesehmacksorgane 
  der 
  Vogel. 
  

   Vortrag, 
  gehalten 
  auf 
  der 
  77. 
  Vers, 
  der 
  Naturf. 
  u. 
  Aerzte 
  in 
  Meran 
  1905. 
  Referat 
  in 
  den 
  

   Verhandlungen 
  der 
  Gessellschaft. 
  

  

  Botezat, 
  E. 
  Morphologie, 
  Physiologie 
  und 
  phylogenetische 
  Bedeutung 
  der 
  Gesehmacks- 
  

   organe 
  der 
  Vogel. 
  Anatomischer 
  Anzeiger, 
  vol. 
  36, 
  1910, 
  pp. 
  428-461. 
  

  

  3 
  Lucas, 
  F. 
  A. 
  The 
  Tongues 
  of 
  Birds. 
  Rep. 
  U. 
  S. 
  Nat. 
  Mus., 
  1895, 
  pp. 
  1003-1020. 
  

  

  