﻿1134. 
  PHILIPPINE 
  ORNITHOLOGY— 
  WORCESTER 
  AND 
  BOURNS. 
  603 
  

  

  because 
  represented 
  by 
  more 
  thau 
  oue 
  species 
  in 
  the 
  archipelago 
  fall 
  

   into 
  Steere's 
  List 
  C, 
  and 
  others 
  decidedly 
  do 
  not. 
  

  

  The 
  revised 
  List 
  B 
  contains 
  a 
  somewhat 
  miscellaneous 
  aggregation 
  

   of 
  forms. 
  Some 
  of 
  the 
  genera 
  are 
  represented 
  by 
  species 
  with 
  wide 
  

   range 
  outside 
  of 
  the 
  Philippines, 
  others 
  by 
  species 
  wliich 
  range 
  widely 
  

   within 
  the 
  group, 
  but 
  extend 
  little 
  if 
  at 
  all 
  beyond 
  its 
  confines, 
  while 
  a 
  

   few 
  genera 
  are 
  represented 
  by 
  species 
  which 
  are 
  confined 
  to 
  a 
  single 
  

   island 
  or 
  small 
  group 
  of 
  islands. 
  

  

  What 
  bearing 
  have 
  the 
  genera 
  included 
  in 
  this 
  list 
  on 
  the 
  question 
  

   in 
  hand? 
  Steere 
  has 
  unhesitatingly 
  assumed 
  that 
  they 
  all 
  afford 
  con- 
  

   firmations 
  of 
  his 
  law, 
  but 
  I 
  am 
  unable 
  to 
  follow 
  him 
  in 
  this. 
  Where 
  

   genera 
  happen 
  to 
  have 
  but 
  a 
  single 
  species 
  in 
  the 
  Philippines, 
  but 
  have 
  

   additional 
  species 
  in 
  other 
  countries, 
  with 
  their 
  ranges 
  overlapping, 
  

   they 
  manifestly 
  can 
  not 
  be 
  held 
  to 
  afford 
  confirmation 
  of 
  the 
  law. 
  On 
  

   the 
  other 
  hantl, 
  the 
  evidence 
  afforded 
  by 
  the 
  forms 
  peculiar 
  to 
  the 
  Phil- 
  

   il)pines 
  is 
  by 
  no 
  means 
  in 
  every 
  case 
  unequivocal. 
  The 
  presence 
  of 
  but 
  

   single 
  species 
  of 
  the 
  peculiar 
  genera 
  Dasijlophus 
  and 
  Lepidoiirammns 
  in 
  

   Luzon 
  and 
  the 
  neigliboring 
  small 
  islands, 
  for 
  instance, 
  can 
  hardly 
  be 
  

   explained 
  as 
  due 
  to 
  their 
  being 
  limited 
  by 
  geographical 
  barriers 
  to 
  an 
  

   area 
  so 
  small 
  au<l 
  little 
  diversified 
  as 
  to 
  prevent 
  the 
  formation 
  of 
  addi- 
  

   tional 
  species, 
  for 
  in 
  this 
  same 
  area 
  we 
  find 
  six 
  species 
  of 
  Dicaeum 
  and 
  

   five 
  of 
  Cinni/ris, 
  while 
  six 
  genera 
  are 
  represented 
  by 
  tour 
  species 
  each, 
  

   eleven 
  by 
  three, 
  and 
  no 
  less 
  than 
  twenty-one 
  by 
  two 
  each. 
  In 
  the 
  case 
  

   of 
  genera 
  like 
  Dasylopiius 
  and 
  Lepidogrannnus, 
  then, 
  I 
  believe 
  that 
  the 
  

   explanation 
  of 
  the 
  occurrence 
  of 
  but 
  a 
  single 
  species 
  is 
  to 
  be 
  sought 
  in 
  

   the 
  organisms 
  themselves. 
  It 
  may 
  be 
  that 
  they 
  are 
  generalized 
  forms, 
  

   capable 
  of 
  existing 
  under 
  a 
  variety 
  of 
  conditions, 
  and 
  hence 
  compara- 
  

   tively 
  independent 
  of 
  their 
  environment 
  

  

  But, 
  apart 
  from 
  their 
  miscellaneous 
  character, 
  there 
  is 
  another 
  reason 
  

   for 
  excluding 
  the 
  species 
  of 
  this 
  list 
  from 
  further 
  consideration. 
  If 
  a 
  

   genus 
  is 
  represented 
  by 
  but 
  a 
  single 
  species 
  in 
  a 
  group 
  of 
  islands, 
  it 
  

   manifestly 
  can 
  not 
  have 
  more 
  than 
  one 
  species 
  on 
  any 
  island 
  of 
  the 
  

   grou]>, 
  hence 
  can 
  afford 
  no 
  evidence 
  on 
  the 
  (luestion 
  as 
  to 
  whether 
  or 
  

   not 
  two 
  or 
  more 
  species 
  belonging 
  to 
  the 
  same 
  genus 
  or 
  section 
  of 
  a 
  

   genus 
  may 
  exist 
  in 
  the 
  same 
  place. 
  

  

  I 
  follow 
  Steere 
  in 
  excluding 
  from 
  consideration 
  genera 
  some 
  or 
  all 
  

  

  the 
  species 
  of 
  which 
  are 
  migratory, 
  and 
  under 
  this 
  head 
  I 
  place 
  the 
  

  

  following: 
  

  

  List 
  A. 
  

  

  AnihuH. 
  Alerula. 
  Pliylloscopus. 
  

  

  ChciiIkh. 
  Motacilla. 
  Xanthopygia. 
  

  

  Hemichelidon. 
  Pandion. 
  

  

  Lock 
  Stella. 
  Pericrocotna. 
  

  

  Lanius 
  I 
  exclude 
  from 
  this 
  list;, 
  believing 
  that 
  all 
  the 
  species 
  recorded 
  

   from 
  the 
  l*hilippines 
  are 
  resident 
  there. 
  

  

  This 
  brings 
  us 
  to 
  Steere's 
  List 
  0, 
  or 
  the 
  list 
  of 
  genera 
  with 
  two 
  or 
  

   more 
  s])ecies 
  which 
  have 
  but 
  one 
  species 
  in 
  a 
  place. 
  Of 
  the 
  genera 
  

  

  