﻿38 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.96 
  

  

  Color. 
  — 
  Face, 
  forehead, 
  top 
  of 
  head, 
  and 
  in 
  some 
  specimens 
  back 
  

   of 
  neck 
  and 
  shoulders 
  black; 
  anterior 
  part 
  of 
  crown 
  patch 
  more 
  or 
  

   less 
  suffused 
  with 
  cinnamon-buff, 
  owing 
  to 
  light 
  basal 
  color 
  of 
  hairs, 
  

   and 
  tending 
  to 
  form 
  a 
  transverse 
  band 
  across 
  forehead 
  ; 
  side 
  whiskers 
  

   on 
  face 
  light 
  buff 
  to 
  cream-buff; 
  upperparts 
  in 
  general 
  buckthorn 
  

   brown 
  to 
  Mars 
  brown, 
  sparsely 
  or 
  noticeably 
  intermixed 
  with 
  blackish 
  

   hairs 
  (especially 
  on 
  midline 
  of 
  back 
  in 
  some 
  individuals) 
  ; 
  belly 
  honey 
  

   yellow 
  to 
  tawny, 
  extending 
  downward 
  on 
  inner 
  surfaces 
  of 
  legs 
  to 
  

   ankles, 
  and 
  a 
  lighter 
  tone 
  near 
  cinnamon-buff 
  extending 
  downward 
  

   on 
  inner 
  surfaces 
  of 
  arms 
  to 
  wrists; 
  outer 
  surfaces 
  of 
  arms 
  and 
  legs 
  

   usually 
  black 
  (in 
  some 
  individuals 
  restricted 
  more 
  or 
  less 
  to 
  elbow 
  

   and 
  knee 
  patches) 
  ; 
  side 
  whiskers 
  on 
  face 
  light 
  buff 
  to 
  cream 
  buff; 
  

   tail 
  usually 
  sharply 
  bicolor, 
  black 
  or 
  dusky 
  above 
  to 
  tip 
  and 
  tawny 
  

   below 
  to 
  callosity 
  (when 
  otherwise, 
  mixed 
  light 
  and 
  dark 
  hairs 
  cover 
  

   the 
  tail 
  above 
  and 
  below) 
  . 
  

  

  Skull. 
  — 
  About 
  as 
  in 
  fanmnensis., 
  averaging 
  somewhat 
  broader 
  than 
  

   in 
  geoffroyi 
  or 
  vellerosus. 
  

  

  Meamremsnts. 
  — 
  No 
  external 
  measurements 
  available. 
  Skull: 
  An 
  

   adult 
  male 
  from 
  Peiia 
  Blanca 
  : 
  Greatest 
  length, 
  109.3 
  ; 
  orbital 
  breadth, 
  

   59.4; 
  postorbital 
  constriction, 
  49; 
  width 
  of 
  brain 
  case, 
  58.6; 
  zygomatic 
  

   breadth, 
  69.6; 
  maxillary 
  tooth 
  row, 
  28.4. 
  Two 
  adult 
  females 
  from 
  

   Lavala 
  and 
  Tuma, 
  Nicaragua, 
  respectively 
  : 
  Greatest 
  length, 
  117.3, 
  112; 
  

   orbital 
  width, 
  64.2, 
  60.2; 
  postorbital 
  constriction, 
  51.1, 
  51; 
  width 
  of 
  

   brain 
  case, 
  62.8, 
  59.8 
  ; 
  zygomatic 
  breadth, 
  71.4, 
  65 
  ; 
  maxillary 
  tooth 
  row, 
  

   29.6, 
  28.4. 
  

  

  Remarks. 
  — 
  A. 
  geoffroyi 
  front 
  atus 
  is 
  assumed 
  to 
  be 
  a 
  recognizable 
  

   subspecies, 
  although 
  aside 
  from 
  the 
  type 
  in 
  the 
  British 
  Museum, 
  from 
  

   northwestern 
  Costa 
  Rica, 
  little 
  is 
  definitely 
  known 
  of 
  its 
  characters 
  or 
  

   distribution. 
  Certain 
  specimens 
  from 
  Costa 
  Rica 
  without 
  definite 
  

   locality, 
  and 
  from 
  various 
  localities 
  in 
  Nicaragua, 
  are 
  tentatively 
  re- 
  

   ferred 
  to 
  frontatus., 
  although 
  in 
  none 
  of 
  these 
  is 
  the 
  black 
  on 
  the 
  head 
  

   so 
  restricted 
  as 
  in 
  the 
  type 
  as 
  figured 
  by 
  Gray 
  {op. 
  cit.). 
  The 
  color 
  

   pattern 
  in 
  this 
  form 
  suggests 
  close 
  relationship 
  to 
  geoffroyi^ 
  which 
  

   might 
  also 
  be 
  expected 
  on 
  geographic 
  grounds. 
  A 
  very 
  young 
  individ- 
  

   ual 
  (U. 
  S. 
  N. 
  M. 
  No. 
  61208) 
  from 
  Costa 
  Rica, 
  without 
  definite 
  locality, 
  

   closely 
  resembles 
  Gray's 
  figure 
  just 
  mentioned 
  in 
  light 
  coloration. 
  A 
  

   skull 
  of 
  an 
  old 
  female 
  from 
  Lavala, 
  Nicaragua 
  (A. 
  M. 
  N. 
  H. 
  No. 
  

   28419), 
  is 
  one 
  of 
  the 
  largest 
  examined 
  from 
  anywhere 
  in 
  Middle 
  

   America. 
  

  

  Specimens 
  examined. 
  — 
  Total 
  number, 
  38, 
  as 
  folloAvs 
  : 
  Costa 
  Rica 
  : 
  3 
  

   (without 
  definite 
  locality) 
  . 
  Nicaragua 
  : 
  Lavala, 
  2 
  (skulls 
  only, 
  A. 
  M. 
  

   N. 
  H.) 
  ; 
  Peiia 
  Blanca, 
  3 
  (A. 
  M. 
  N. 
  H.) 
  ; 
  Rio 
  Siquia, 
  2 
  (skulls 
  only, 
  

   U. 
  M. 
  M. 
  Z.) 
  ; 
  Rio 
  Yoya, 
  a 
  tributary 
  of 
  Rio 
  Princapolca, 
  25 
  (skulls 
  

   only, 
  A. 
  H. 
  S.) 
  ; 
  Tuma, 
  2 
  (skulls 
  only, 
  A. 
  M. 
  N. 
  H.) 
  ; 
  Uluce, 
  1 
  

   (A. 
  M. 
  N. 
  H.). 
  

  

  