﻿338 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol. 
  as 
  

  

  size 
  the 
  diagnostic 
  characters 
  of 
  albifrons 
  and 
  render 
  certain 
  its 
  

   identification 
  and 
  distinction 
  from 
  any 
  other 
  species 
  of 
  Cebus. 
  Fur- 
  

   thermore, 
  the 
  name 
  albifrons 
  is 
  based 
  on 
  monkeys 
  seen 
  by 
  Hmnboldt 
  

   in 
  their 
  native 
  habitat. 
  Thus, 
  it 
  is 
  mandatory 
  to 
  regard 
  the 
  brown 
  

   pale-fronted 
  Cebus 
  of 
  the 
  upper 
  Rio 
  Orinoco 
  region 
  as 
  the 
  typical 
  

   representative 
  of 
  this 
  widely 
  distributed 
  species. 
  

  

  Pusch's 
  treatment 
  of 
  albifrons 
  is 
  novel. 
  He 
  gave 
  its 
  distribution 
  as 
  

   "Rio 
  de 
  Janeiro, 
  Sao 
  Paulo, 
  Bahia." 
  This 
  range 
  not 
  only 
  excludes 
  the 
  

   type 
  locality 
  but 
  is 
  wholly 
  outside 
  the 
  range 
  of 
  the 
  species. 
  Pusch 
  had 
  

   no 
  specimens 
  of 
  albifrons, 
  but 
  he 
  listed 
  as 
  synonyms 
  of 
  it 
  a 
  miscellaneous 
  

   collection 
  of 
  "tufted" 
  cebids 
  that 
  have 
  nothing 
  in 
  common 
  with 
  true 
  

   albifrons 
  apart 
  from 
  belonging 
  to 
  the 
  same 
  genus, 
  Pusch's 
  bases 
  for 
  

   distinguishing 
  "albifrons" 
  from 
  all 
  other 
  species 
  of 
  Cebus 
  were 
  his 
  

   observation 
  that 
  other 
  monkeys 
  "arch 
  their 
  backs 
  like 
  cats 
  while 
  C. 
  

   albifrons 
  always 
  maintains 
  its 
  back 
  stiff 
  and 
  straight. 
  It 
  does 
  not 
  

   seem 
  to 
  climb 
  upward 
  for 
  any 
  great 
  distance. 
  It 
  prefers, 
  instead, 
  a 
  

   position 
  with 
  its 
  head 
  uppermost. 
  When 
  not 
  grasping 
  anything, 
  C. 
  

   apella 
  always 
  supports 
  itself 
  with 
  its 
  hands 
  while 
  sitting. 
  C. 
  albifrons, 
  

   on 
  the 
  contrary, 
  prefers 
  to 
  lock 
  its 
  arms 
  over 
  its 
  head 
  while 
  in 
  a 
  sitting 
  

   posture. 
  On 
  the 
  ground, 
  C. 
  apella 
  chacoensis 
  and 
  C. 
  albifrons 
  walk 
  

   with 
  a 
  quiet 
  evenly 
  paced 
  gait, 
  while 
  the 
  common 
  apella 
  (griseus 
  group) 
  

   scurries 
  about 
  restlessly 
  with 
  its 
  back 
  highly 
  arched. 
  The 
  explanation 
  

   for 
  this 
  may 
  be 
  that 
  the 
  latter 
  species 
  was 
  better 
  fed 
  and 
  the 
  former 
  

   feared 
  its 
  superior 
  strength." 
  These 
  compelling 
  arguments 
  for 
  dis- 
  

   tinction 
  of 
  the 
  species 
  concerned 
  were 
  based 
  on 
  the 
  quoted 
  author's 
  

   notes 
  on 
  menagerie 
  animals 
  of 
  unknown 
  origins. 
  

  

  Simla 
  hypoleuca 
  Humboldt 
  (1812, 
  p. 
  336). 
  The 
  original 
  descrip- 
  

   tion 
  (reproduced 
  in 
  full 
  under 
  the 
  subspecific 
  heading 
  in 
  this 
  report) 
  is 
  

   obviously 
  that 
  of 
  a 
  brown 
  pale-fronted 
  Cebus 
  of 
  the 
  albifrons 
  group. 
  

   Nevertheless, 
  hypoleucus 
  has 
  been 
  considered 
  by 
  most 
  authors 
  as 
  

   identical 
  with 
  the 
  black 
  white-fronted 
  C. 
  capucinus 
  Linnaeus, 
  1758. 
  

   This 
  error 
  in 
  identification 
  was 
  initiated 
  and 
  perpetuated 
  by 
  authors 
  

   who 
  either 
  failed 
  to 
  examine 
  carefully 
  the 
  original 
  description 
  of 
  

   hypoleucus 
  or 
  did 
  not 
  distinguish 
  between 
  the 
  brown 
  capucinus 
  of 
  

   authors 
  and 
  the 
  black 
  white-fronted 
  capucinus 
  of 
  Linnaeus, 
  1758. 
  

   E. 
  Geoff 
  roy 
  (1812, 
  p. 
  Ill) 
  doubtfully 
  referred 
  hypoleucus 
  ( 
  and 
  Buffon's 
  

   sa'i 
  d 
  gorge 
  blanche) 
  to 
  his 
  "capucinus," 
  the 
  brown 
  species. 
  Subsequent 
  

   authors, 
  notably 
  Pucheran 
  (1856, 
  p. 
  34) 
  and 
  Elliot 
  (1907c, 
  p. 
  227), 
  

   follow^ed 
  by 
  indiscriminately 
  regarding 
  hypoleucus 
  as 
  identical 
  with 
  

   true 
  capucinus! 
  If 
  Humboldt 
  ever 
  saw 
  a 
  true 
  Cebus 
  capucinus 
  during 
  

   the 
  course 
  of 
  his 
  travels 
  in 
  tropical 
  America, 
  he 
  never 
  revealed 
  it 
  in 
  

   any 
  of 
  his 
  numerous 
  writings. 
  He 
  reviewed 
  all 
  species 
  of 
  Cebus 
  known 
  

   to 
  him, 
  and 
  nowhere 
  throughout 
  the 
  text 
  of 
  his 
  accounts 
  can 
  be 
  found 
  

   any 
  allusions 
  to 
  a 
  black 
  white-fronted 
  monkey. 
  All 
  cebids 
  desci'ibed 
  

  

  