﻿10 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  vol.96 
  

  

  N. 
  Underi>arts 
  normally 
  silvery 
  whitish 
  ; 
  brownish 
  black 
  of 
  head 
  and 
  

   neck 
  passing 
  gradually 
  through 
  cinnamon-drab 
  on 
  upper 
  back 
  

   to 
  near 
  olive-buff 
  on 
  lumbar 
  region, 
  the 
  light 
  drab 
  extending 
  

   along 
  median 
  line 
  to 
  base 
  of 
  tail 
  ; 
  side 
  whiskers 
  on 
  face 
  whit- 
  

   ish. 
  (Quintana 
  Roo, 
  Yucatan, 
  and 
  northeastern 
  Guate- 
  

   mala.) 
  yucatanensis 
  

  

  NN. 
  Underparts 
  not 
  normally 
  silvery 
  whitish. 
  

  

  O. 
  Upperparts 
  dark, 
  especially 
  on 
  head, 
  neck, 
  and 
  upper 
  back, 
  and 
  

   more 
  uniformly 
  overlaid 
  with 
  black 
  ; 
  lumbar 
  region 
  more 
  or 
  

   less 
  noticeably 
  suffused 
  with 
  cinnamon 
  ; 
  pelage 
  typically 
  

   longer 
  and 
  denser 
  ; 
  underside 
  of 
  neck 
  and 
  throat 
  mixed 
  brown- 
  

   ish 
  and 
  buffy 
  ; 
  rest 
  of 
  underparts 
  including 
  at 
  least 
  inner 
  sur- 
  

   faces 
  of 
  upper 
  portions 
  of 
  limbs 
  pinkish 
  buff 
  to 
  cinnamon-buff, 
  

   becoming 
  cinnamon 
  or 
  rusty 
  along 
  sides 
  of 
  body 
  ; 
  crown 
  cap 
  

   blackish 
  ; 
  side 
  whiskers 
  on 
  face 
  blackish. 
  (Alta 
  Vera 
  Paz, 
  

  

  Guatemala.) 
  pan 
  

  

  00. 
  Upperparts 
  lighter, 
  distinctly 
  bicolored 
  ; 
  head, 
  neck, 
  and 
  

   upper 
  back 
  brownish 
  black 
  ; 
  lumbar 
  region 
  cinnamon-buff 
  

   or 
  cinnamon, 
  darkened 
  along 
  midline 
  by 
  overlying 
  blackish 
  

   hairs 
  ; 
  underside 
  of 
  neck 
  and 
  throat 
  varying 
  from 
  grayish 
  

   to 
  a 
  mixture 
  of 
  buff-gray 
  and 
  brown 
  ; 
  underparts, 
  includ- 
  

   ing 
  inner 
  surfaces 
  of 
  arms 
  in 
  a 
  strip 
  narrowing 
  from 
  

   armpit 
  to 
  a 
  point 
  near 
  elbows 
  and 
  on 
  inner 
  surfaces 
  of 
  

   legs 
  to 
  near 
  ankles, 
  varying 
  from 
  pinkish 
  buff 
  to 
  cin- 
  

   namon, 
  becoming 
  near 
  cinnamon 
  on 
  sides 
  of 
  body 
  ; 
  crown 
  

   cap 
  blackish 
  ; 
  side 
  whiskers 
  on 
  face 
  dull 
  whitish 
  or 
  yellow- 
  

   ish. 
  (Honduras 
  and 
  El 
  Salvador 
  northward 
  through 
  

   Guatemala 
  to 
  southeastern 
  Oaxaca 
  and 
  the 
  Isthmus 
  of 
  

   Tehuantepec 
  and 
  along 
  east 
  coast 
  of 
  Mexico 
  to 
  eastern 
  

  

  San 
  Luis 
  Potosl.) 
  vellerosus 
  

  

  MM. 
  Upper 
  back 
  not 
  distinctly 
  darker 
  than 
  lumbar 
  region 
  of 
  back 
  ; 
  

   general 
  coloration 
  of 
  upperparts, 
  including 
  outer 
  surfaces 
  of 
  

   fore 
  and 
  hind 
  limbs, 
  as 
  well 
  as 
  upper 
  surface 
  of 
  tail, 
  dusky, 
  

   the 
  darker 
  hairs 
  nearly 
  sooty 
  black 
  on 
  distal 
  two-thirds 
  and 
  

   old 
  gold 
  on 
  basal 
  third, 
  and 
  thinly 
  interspersed 
  with 
  these 
  

   on 
  head, 
  neck, 
  back, 
  thighs, 
  and 
  upper 
  surface 
  of 
  tail 
  are 
  

   old 
  gold 
  or 
  silvery 
  hairs 
  ; 
  coloration 
  of 
  upperparts 
  further 
  

   modified 
  by 
  lighter 
  hair 
  bases 
  showing 
  through 
  ; 
  a 
  partially 
  

   concealed 
  huffy 
  spot 
  on 
  forehead 
  ; 
  hairs 
  on 
  belly, 
  inner 
  sur- 
  

   faces 
  of 
  hind 
  limbs, 
  and 
  under 
  surface 
  of 
  tail 
  dull 
  cinnamon- 
  

   buff 
  tipped 
  with 
  sooty 
  black. 
  (Rio 
  Tuyra 
  Valley 
  of 
  eastern 
  

   Panama.) 
  grisescens 
  

  

  