﻿350 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.98 
  

  

  apparent 
  than 
  real. 
  Little 
  or 
  no 
  collecting 
  has 
  been 
  done 
  in 
  most 
  of 
  

   the 
  area 
  representing 
  the 
  hiatus. 
  The 
  insular 
  C. 
  a. 
  trinitatis 
  is 
  com- 
  

   pletely 
  cut 
  off 
  from 
  its 
  relatives 
  by 
  the 
  northern 
  portion 
  of 
  Venezuela. 
  

   It 
  may 
  have 
  been 
  introduced 
  into 
  Trinidad 
  from 
  Brazil 
  or 
  from 
  the 
  

   interior 
  of 
  Venezuela 
  or 
  Colombia. 
  C. 
  a. 
  aequatorialis 
  of 
  western 
  

   Ecuador 
  is 
  also, 
  apparently, 
  a 
  completely 
  isolated 
  race. 
  However, 
  a 
  

   continuous 
  distribution 
  of 
  the 
  species 
  along 
  the 
  coast 
  of 
  western 
  

   Colombia 
  between 
  the 
  type 
  localities 
  of 
  aequatorialis 
  and 
  hypoleucus 
  

   of 
  northern 
  Colombia 
  may 
  be 
  postulated. 
  If 
  this 
  assumption 
  proves 
  

   wrong, 
  the 
  probability 
  of 
  an 
  erstwhile 
  low 
  elevation 
  trans-Andean 
  

   continuity 
  of 
  range 
  between 
  aequatorialis 
  and 
  upper 
  Amazonian 
  repre- 
  

   sentatives 
  of 
  albifrons 
  must 
  be 
  considered. 
  In 
  spite 
  of 
  the 
  broken 
  

   distributional 
  pattern 
  of 
  the 
  species, 
  physical 
  characters 
  of 
  the 
  

   forms 
  referred 
  to 
  albifrons 
  are 
  such 
  as 
  to 
  leave 
  no 
  doubt 
  of 
  their 
  

   conspecificity. 
  

  

  Coloration.— 
  Face 
  with 
  light 
  down 
  of 
  brown 
  to 
  silvery 
  hairs, 
  longer 
  

   hairs 
  sparsely 
  covering 
  upper 
  lip; 
  cheeks 
  and 
  point 
  of 
  chin 
  white 
  to 
  

   cinnamon. 
  Superciliary 
  region 
  broadly 
  whitish 
  to 
  cinnamon, 
  the 
  

   color 
  extending 
  round 
  sides 
  of 
  face, 
  encircling 
  ears 
  and 
  continuous 
  

   with 
  white 
  or 
  ochraceous 
  of 
  throat, 
  sides 
  and 
  ventral 
  surface 
  of 
  neck, 
  

   upper 
  portion 
  of 
  chest, 
  and 
  part 
  of 
  shoulder. 
  In 
  males, 
  and 
  females 
  

   without 
  frontal 
  diadem, 
  cap 
  grayish 
  brown 
  to 
  dark 
  brown, 
  usually 
  

   darker 
  than 
  median 
  dorsal 
  area, 
  broadly 
  outlined 
  in 
  front 
  and 
  often 
  

   with 
  a 
  median 
  point 
  or 
  line 
  extending 
  across 
  whitish 
  superciliary 
  

   region. 
  Back 
  from 
  Light 
  Ochraceous-Buff 
  to 
  reddish 
  brown, 
  the 
  

   hairs 
  usually 
  without 
  sharply 
  contrasted 
  annulations 
  or 
  distinct 
  sub- 
  

   terminal 
  banding; 
  median 
  dorsal 
  region 
  usually 
  warmer 
  or 
  darker 
  

   than 
  sides 
  of 
  back. 
  Lateral 
  fringe 
  like 
  side 
  or 
  middle 
  of 
  back. 
  Lower 
  

   part 
  of 
  chest 
  and 
  belly 
  sparsely 
  haired 
  yellowish 
  to 
  reddish. 
  Color 
  of 
  

   upper 
  arm 
  like 
  adjacent 
  regions 
  of 
  shoulder, 
  neck 
  and 
  side 
  of 
  trunk; 
  

   forearm 
  drab 
  or 
  yellowish 
  to 
  reddish 
  brown, 
  the 
  hairs 
  paler 
  basally, 
  

   frequently 
  broadly 
  paler 
  or 
  silvery 
  apically, 
  creating 
  a 
  "hoar-frosted" 
  

   effect. 
  Hands 
  above 
  grayish 
  to 
  dark 
  brown, 
  not 
  black. 
  Thighs 
  like 
  

   adjacent 
  parts 
  of 
  body; 
  forelegs 
  and 
  feet 
  like 
  forearms 
  and 
  hands. 
  

   Upper 
  proximal 
  portion 
  of 
  tail 
  like 
  median 
  dorsal 
  region, 
  or 
  "hoar- 
  

   frosted," 
  terminally 
  paler, 
  undersurface 
  like 
  sides 
  of 
  back 
  proximally, 
  

   terminally 
  paler, 
  becoming 
  yellowish 
  or 
  whitish. 
  

  

  Variations. 
  — 
  The 
  subspecies 
  are 
  differentiated 
  on 
  the 
  basis 
  of 
  color 
  

   and 
  color 
  pattern; 
  color 
  of 
  limbs, 
  especially 
  in 
  relationship 
  to 
  that 
  of 
  

   the 
  trunk, 
  is 
  one 
  of 
  the 
  more 
  important 
  diagnostic 
  characters. 
  These 
  

   characters 
  are 
  fairly 
  constant 
  in 
  any 
  one 
  series 
  of 
  adults 
  irrespective 
  

   of 
  age 
  and 
  sex. 
  Usually 
  subadults 
  and 
  young 
  individuals 
  show 
  paler 
  

   tones 
  of 
  the 
  same 
  colors 
  distributed 
  in 
  approximately 
  the 
  same 
  way 
  

   as 
  in 
  adults. 
  Sexual 
  differences 
  and 
  what 
  appear 
  to 
  be 
  light 
  and 
  dark 
  

  

  