﻿100 
  On 
  Siriffs 
  and 
  Hnmming-hlrds. 
  

  

  59. 
  Tico 
  pairs 
  of 
  s^yriugeal 
  niiis- 
  50. 
  Several 
  pairs 
  of 
  syringeal 
  

  

  cles; 
  sterno-trachea/eshemg 
  present. 
  muscles 
  (Macgillivray) 
  ; 
  sterno- 
  

   Musciilature 
  of 
  the 
  syrinx 
  differing 
  tracheales 
  absent 
  (rare 
  in 
  birds). 
  

   entirely 
  from 
  anything 
  seen 
  in 
  the 
  Entire 
  syrinx 
  and 
  its 
  muscles 
  differ- 
  

   Trochili. 
  eut 
  from 
  those 
  of 
  any 
  l^nown 
  Swift. 
  

  

  CO. 
  Morphology 
  of 
  the 
  liver 
  GO. 
  Morphology 
  of 
  the 
  /iV«- 
  quite 
  

  

  agreeing 
  in 
  the 
  main 
  with 
  the 
  difterent 
  from 
  that 
  of 
  the 
  Swallows. 
  

   Swallows. 
  Lobes 
  so 
  disposed 
  as 
  to 
  entirely 
  hide 
  

  

  the 
  other 
  abdominal 
  viscera 
  when 
  

  

  viewed 
  upon 
  the 
  ventral 
  aspect. 
  

  

  Gl. 
  Morphology 
  of 
  the 
  «?;'iVe 
  di- 
  Gl. 
  Morphology 
  of 
  the 
  eiitire 
  

  

  gestive 
  tract 
  agreeing 
  in 
  the 
  main 
  digestive 
  tract 
  strikingly 
  peculiar. 
  

  

  with 
  that 
  of 
  the 
  Fasseres, 
  and 
  espe- 
  Intestine 
  of 
  comparatively 
  largo 
  

  

  cially 
  the 
  Swallows. 
  calibre 
  and 
  proportions 
  ; 
  stomach 
  

  

  remarJitthlif 
  reduced 
  in 
  size 
  ; 
  rectal 
  

  

  cloaca 
  bulbous. 
  

  

  It 
  is 
  a 
  fact 
  that 
  intestinal 
  cseoa 
  arc 
  absent 
  in 
  hotli 
  CypseJl 
  and 
  

   Trochili. 
  but 
  tliey 
  are 
  also 
  present 
  in 
  some 
  Parrots 
  and 
  absent 
  

   in 
  others 
  of 
  the 
  same 
  group. 
  As 
  a 
  character, 
  it 
  would 
  seem, 
  

   these 
  organs 
  are 
  not 
  of 
  any 
  very 
  great 
  classificatory 
  value. 
  

  

  The 
  comparative 
  notes 
  presented 
  in 
  the 
  present 
  paper 
  have 
  

   been 
  carefully 
  selected 
  from 
  my 
  former 
  writings 
  upon 
  this 
  sub- 
  

   ject, 
  and 
  a 
  reading 
  of 
  what 
  has 
  been 
  written 
  about 
  Swifts, 
  Swal- 
  

   lows, 
  and 
  Humming-birds 
  for 
  tlie 
  last 
  five 
  years, 
  and, 
  finally, 
  

   based 
  on 
  a 
  critical 
  examination 
  of 
  much 
  additional 
  material. 
  

   It 
  will 
  be 
  seen 
  that 
  I 
  have 
  selected 
  only 
  61 
  anatomical 
  points, 
  

   but 
  they 
  are 
  each 
  and 
  all 
  points 
  of 
  "definite 
  diiference," 
  and 
  

   to 
  my 
  mind 
  clearly 
  establish 
  the 
  fact 
  that 
  the 
  Cypseli 
  and 
  

   Trochili 
  are 
  not, 
  morphologicaliy 
  speaking, 
  related 
  groups 
  of 
  

   birds. 
  It 
  will 
  further 
  be 
  seen 
  that 
  the 
  structures 
  selected 
  

   for 
  comparison 
  have 
  been 
  found 
  in 
  nearly 
  every 
  system 
  of 
  

   the 
  economy, 
  and 
  there 
  can 
  be 
  no 
  doubt 
  that 
  by 
  the 
  aid 
  of 
  

   the 
  dissecting-lens 
  many 
  others 
  would 
  come 
  to 
  light. 
  

  

  It 
  gives 
  me 
  pleasure 
  to 
  submit 
  these 
  61 
  important 
  struc- 
  

   tural 
  differences 
  existing 
  between 
  the 
  Cypseli 
  and 
  the 
  Trochili 
  

   to 
  the 
  thoughtful 
  systematist 
  in 
  ornithology, 
  confident 
  as 
  I 
  am 
  

   that 
  after 
  their 
  weight 
  has 
  been 
  duly 
  appreciated 
  there 
  will 
  no 
  

   longer 
  be 
  any 
  doubt 
  in 
  his 
  mind 
  that 
  not 
  only 
  is 
  a 
  typical 
  Swift 
  

   a 
  widely 
  different 
  kind 
  of 
  bird 
  from 
  a 
  Humming-bird, 
  but 
  

   that 
  in 
  reality, 
  after 
  all, 
  the 
  Swifts 
  are 
  but 
  greatly 
  modified 
  

   Swallows, 
  as 
  so 
  much 
  in 
  their 
  structr-re 
  undoubtedly 
  indicates. 
  

  

  