﻿MAMMALS 
  OF 
  NORTHERN 
  COLOMBIA 
  — 
  ^HERSHKOVITZ 
  401 
  

  

  Each 
  of 
  the 
  many 
  names 
  proposed 
  for 
  local 
  forms 
  of 
  the 
  genus 
  has 
  

   been 
  based 
  in 
  part 
  or 
  in 
  whole 
  on 
  the 
  structure 
  of 
  the 
  most 
  variable 
  

   parts 
  of 
  the 
  skull 
  and 
  the 
  equally 
  variable 
  pattern 
  of 
  head 
  markings. 
  

   Real 
  or 
  imaginary 
  anomalies 
  have 
  also 
  figured 
  among 
  "specific" 
  

   characters 
  of 
  named 
  forms. 
  External 
  ears 
  in 
  the 
  first 
  described 
  

   Simia 
  trivirgata 
  were 
  said 
  to 
  be 
  nearly 
  obsolete. 
  The 
  last 
  described, 
  

   Aotus 
  bidentatus 
  Lonnberg, 
  is 
  based 
  on 
  an 
  anomalous 
  individual 
  with 
  

   a 
  single 
  pair 
  of 
  upper 
  incisors. 
  The 
  author 
  has 
  examined 
  the 
  type 
  

   specimens 
  of 
  Aotus 
  in 
  the 
  British 
  Museum 
  (nigriceps, 
  lanius, 
  senex, 
  

   gularis, 
  miconax, 
  microdon, 
  boliviensis) 
  and 
  those 
  conserved 
  in 
  the 
  

   Paris 
  Museum 
  (lemurinus, 
  oseryi, 
  spixii, 
  and 
  Nocthora 
  trivirgata 
  

   Cuvier, 
  not 
  Humboldt). 
  No 
  valid 
  specific 
  differences 
  were 
  noted 
  

   between 
  any 
  of 
  these. 
  On 
  the 
  contrary, 
  individual 
  variation 
  among 
  

   these 
  types 
  is 
  such 
  that 
  some 
  of 
  them 
  differ 
  less 
  from 
  each 
  other 
  than 
  

   they 
  do 
  from 
  their 
  respective 
  cotypes 
  or 
  topotypes. 
  Characters 
  de- 
  

   vised 
  by 
  Tate 
  for 
  members 
  of 
  the 
  "aversus 
  division" 
  (included: 
  lanius, 
  

   griseimembra, 
  pervigilis, 
  zonalis, 
  bipunctatus, 
  lemurinus) 
  and 
  for 
  the 
  

   "trivirgatus 
  division" 
  (included: 
  infulatus, 
  nigripes 
  [nomen 
  nudum], 
  

   senex, 
  vocijerans, 
  oseryi, 
  gularis, 
  spixi 
  [sic], 
  miconax, 
  nigriceps) 
  appear 
  

   to 
  have 
  been 
  derived 
  from 
  specimens 
  selected 
  at 
  random 
  and 
  from 
  

   type 
  specimens 
  preserved 
  in 
  the 
  American 
  Museum 
  of 
  Natural 
  

   History. 
  Type 
  specimens 
  in 
  the 
  British 
  and 
  Paris 
  Museums 
  do 
  not 
  

   yield 
  to 
  Tate's 
  characterizations. 
  At 
  best, 
  some 
  of 
  these 
  types 
  

   straddle 
  both 
  his 
  divisions. 
  Cranial 
  characters 
  described 
  by 
  various 
  

   authors 
  for 
  distinguishing 
  the 
  "species," 
  must 
  be 
  discounted 
  in 
  their 
  

   entirety. 
  Large 
  series 
  of 
  comparable 
  skulls 
  demonstrate 
  their 
  unre- 
  

   liability. 
  External 
  variations 
  among 
  night 
  monkeys 
  include 
  a 
  gray 
  

   and 
  brown 
  color 
  phase 
  with 
  all 
  stages 
  of 
  intermediacy 
  ; 
  pelage 
  short, 
  

   soft 
  and 
  dense 
  to 
  long, 
  coarse 
  and 
  lax 
  ; 
  head 
  markings 
  vary 
  individually 
  

   to 
  such 
  an 
  extent 
  that 
  no 
  one 
  pattern 
  is 
  found 
  to 
  be 
  locally 
  constant. 
  

   More 
  often 
  than 
  not 
  head 
  markings 
  described 
  from 
  a 
  dried 
  skin 
  are 
  

   determined 
  by 
  the 
  manner 
  in 
  which 
  the 
  skin 
  was 
  prepared 
  and 
  dried; 
  

   length 
  of 
  pelage 
  further 
  defines 
  the 
  ultimate 
  appearance 
  of 
  head 
  

   markings 
  in 
  the 
  dried 
  skin. 
  

  

  There 
  appear 
  to 
  be 
  several 
  well-marked 
  geographic 
  forms 
  of 
  the 
  

   genotype 
  and 
  only 
  species. 
  Aotus 
  trivirgatus 
  trivirgatus 
  Humboldt 
  ^ 
  

   is 
  the 
  name 
  for 
  the 
  night 
  monkey 
  of 
  the 
  Orinoco 
  and 
  a 
  greater 
  part 
  

   of 
  the 
  northern 
  and 
  upper 
  Amazonian 
  regions. 
  A. 
  t. 
  azarae 
  Hum- 
  

   boldt 
  (miriquouina 
  Geoft'roy 
  antedated), 
  a 
  well-defined 
  form, 
  occurs 
  

   in 
  the 
  Chaco 
  of 
  Paraguay, 
  Brazil, 
  Bolivia, 
  and 
  Argentina. 
  A. 
  t. 
  roberti 
  

   Dollman 
  of 
  the 
  Serra 
  da 
  Chapada, 
  Matto 
  Grosso, 
  Brazil, 
  grades 
  into 
  

   azarae. 
  The 
  brownish 
  A. 
  t. 
  lemurinus 
  Geoffroy 
  is 
  the 
  night 
  monkey 
  

  

  « 
  With 
  synonyms 
  humboldtii 
  Illiger, 
  durucnli 
  Lesson, 
  infulatus 
  Olfers 
  (antedates 
  infvlatxLi 
  Kuhl) 
  , 
  /eZinti* 
  

   Spix, 
  vociferans 
  Spix, 
  commersonii 
  Vigors 
  and 
  Horsfleld, 
  oseryi 
  Geoffroy 
  and 
  DevUle, 
  gidaTis 
  Dollman, 
  senex 
  

   Dollman, 
  and 
  spizii 
  Pucheran, 
  based 
  on 
  a 
  menagerie 
  specimen 
  of 
  unknown 
  origin. 
  

  

  