﻿ATELEUS 
  27 
  

  

  extending 
  their 
  range 
  into 
  Colombia, 
  the 
  latter 
  going 
  even 
  to 
  Peru. 
  A. 
  

   rufiventris 
  is 
  doubtfully 
  from 
  Panama, 
  the 
  type 
  coming 
  from 
  the 
  Rio 
  

   Atrato 
  in 
  Colombia. 
  In 
  the 
  Guianas, 
  and 
  on 
  the 
  banks 
  of 
  the 
  Orinoco, 
  

   and 
  also 
  on 
  those 
  of 
  the 
  Lower 
  and 
  Upper 
  Amazon 
  with 
  such 
  tribu- 
  

   taries 
  as 
  the 
  Rio 
  Madeira, 
  R. 
  Marmore, 
  R. 
  Guapore 
  and 
  R. 
  Carari, 
  and 
  

   ranging 
  as 
  far 
  to 
  the 
  westward 
  as 
  the 
  Rio 
  Marafion, 
  Peru, 
  A. 
  panis- 
  

   cus 
  occurs. 
  On 
  the 
  Upper 
  Rio 
  Cauca, 
  a 
  tributary 
  of 
  the 
  Orinoco, 
  A. 
  

   variegatus 
  is 
  met 
  with, 
  ranging 
  westward 
  into 
  Peru 
  in 
  the 
  Province 
  

   of 
  Jean 
  de 
  Bracamorros, 
  and 
  at 
  Chayavetas, 
  Nautuas 
  and 
  Elvira, 
  

   Peruvian 
  Amazons. 
  A. 
  marginatus 
  is 
  found 
  in 
  the 
  vicinity 
  of 
  Para, 
  

   Lower 
  Amazon, 
  and 
  on 
  the 
  banks 
  of 
  the 
  Rio 
  Tocantins. 
  Above 
  the 
  

   great 
  rapids 
  of 
  the 
  Orinoco, 
  at 
  Atures 
  and 
  Maypures, 
  A. 
  belzebuth 
  

   occurs 
  ; 
  and 
  in 
  Colombia 
  in 
  the 
  Valley 
  of 
  the 
  Magdalena, 
  A. 
  hybridus 
  

   is 
  supposed 
  to 
  dwell. 
  A. 
  fusciceps 
  has 
  only 
  been 
  met 
  with 
  in 
  the 
  

   trans-Andean 
  districts 
  of 
  Ecuador. 
  There 
  remain 
  two 
  rather 
  doubtful 
  

   species 
  whose 
  habitats 
  are 
  quite 
  unknown, 
  A. 
  grisescens 
  and 
  A. 
  

  

  CUCULLATUS. 
  

  

  KEY 
  TO 
  THE 
  SPECIES. 
  

  

  A. 
  Head 
  and 
  back 
  black. 
  

  

  a. 
  Under 
  parts 
  black. 
  

  

  a! 
  Face 
  flesh 
  color. 
  

  

  a." 
  Forehead, 
  crown 
  and 
  whiskers 
  black. 
  ..A. 
  paniscus. 
  

  

  b" 
  Forehead, 
  crown 
  and 
  whiskers 
  white.A 
  marginatus. 
  

   b! 
  Face 
  black 
  A. 
  ater. 
  

  

  b. 
  Under 
  parts, 
  grayish 
  yellow 
  A. 
  variegatus. 
  

  

  c. 
  Under 
  parts 
  bright 
  rufous 
  A. 
  rufiventris. 
  

  

  B. 
  Head 
  and 
  back 
  mixed 
  black 
  and 
  silvery 
  gray 
  or 
  golden, 
  

   o. 
  Hair 
  on 
  head 
  not 
  projecting 
  over 
  forehead; 
  back 
  

  

  more 
  black 
  than 
  gray 
  A. 
  grisescens. 
  

  

  b. 
  Hair 
  on 
  head 
  projecting 
  over 
  forehead; 
  back 
  more 
  

  

  gray 
  than 
  black 
  A. 
  cucullatus. 
  

  

  C. 
  Head 
  black, 
  back 
  blackish 
  chestnut 
  grading 
  into 
  golden. 
  

  

  a. 
  Under 
  side 
  of 
  arms 
  and 
  legs 
  grayish 
  yellow 
  A. 
  belzebuth. 
  

  

  b. 
  Under 
  side 
  of 
  arms 
  and 
  legs 
  mostly 
  black, 
  yellow 
  

  

  restricted 
  to 
  narrow 
  line 
  On 
  forearm 
  A. 
  pan. 
  

  

  D. 
  Head 
  yellowish 
  wood 
  brown, 
  back 
  black 
  tinged 
  with 
  

  

  burnt 
  umber 
  brown 
  A. 
  fusciceps. 
  

  

  E. 
  Head 
  buff, 
  back 
  grayish 
  drab, 
  (typical) 
  .A. 
  geoifroyi. 
  

  

  F. 
  Head 
  blackish 
  brown, 
  triangular 
  white 
  mark 
  on 
  fore- 
  

  

  head 
  . 
  d. 
  hybridus. 
  

  

  