﻿500 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol.44. 
  

  

  KEY 
  TO 
  THE 
  SPECIES 
  OF 
  MONGOMA. 
  

  

  1. 
  Veins 
  Cu, 
  and 
  Mj 
  distinct 
  at 
  the 
  wing 
  margin 
  disjuncta, 
  new 
  species 
  (Brazil). 
  

  

  Veins 
  Cui 
  and 
  M3 
  not 
  distinct 
  at 
  the 
  wing 
  margin 
  2. 
  

  

  2. 
  Tarsi 
  of 
  all 
  the 
  legs 
  white 
  niveitarsis, 
  new 
  species 
  (Greater 
  Antilles). 
  

  

  Tarsi 
  of 
  all 
  the 
  legs 
  not 
  white 
  3. 
  

  

  3. 
  Cell 
  R2 
  of 
  the 
  wings 
  very 
  long, 
  much 
  longer 
  than 
  cell 
  R5 
  4. 
  

  

  Cell 
  R2 
  of 
  the 
  wings 
  short, 
  about 
  as 
  long 
  as 
  cell 
  R5 
  5. 
  

  

  4. 
  Larger 
  species; 
  length 
  7-8 
  mm 
  manca 
  Williston' 
  (Lesser 
  Antilles). 
  

  

  Small 
  species; 
  length 
  5 
  mm 
  externa, 
  new 
  species 
  (Brazil). 
  

  

  5. 
  Nostigmalspot; 
  ground 
  colorof 
  the 
  body 
  yellow. 
  paZZic?aWilliston'^( 
  Lesser 
  Antilles). 
  

   Stigmal 
  spot 
  distinct; 
  ground 
  color 
  of 
  the 
  body 
  brown. 
  

  

  longifusa. 
  new 
  species 
  (Panama). 
  

  

  MONGOMA 
  DISJUNCTA, 
  new 
  species. 
  

  

  Antennae 
  brown; 
  body 
  and 
  legs 
  light 
  brownish-yellow; 
  veins 
  M3 
  

   and 
  Cui 
  distinct 
  at 
  the 
  wing 
  margin. 
  

  

  Female. 
  — 
  Length, 
  11.6 
  mm.; 
  mng, 
  10.2 
  mm; 
  fore 
  leg, 
  femur 
  11.8 
  

   mm.; 
  tibia 
  14; 
  tarsus 
  12.6; 
  hind 
  leg, 
  femur 
  12.4 
  mm; 
  tibia 
  12.4; 
  

   tarsus 
  9.6. 
  Head: 
  rostrum 
  and 
  palpi 
  brown, 
  the 
  terminal 
  segment 
  

   s 
  rather 
  darker; 
  antennae 
  brown; 
  front, 
  vertex, 
  occiput 
  and 
  genae 
  

   browTiish-yello 
  w 
  . 
  

  

  Thorax 
  : 
  prothorax 
  light 
  brownish, 
  its 
  pleura 
  darker 
  brown. 
  Meso- 
  

   notum: 
  praescutum 
  dull 
  yellow 
  with 
  a 
  faint 
  brownish 
  tinge 
  ; 
  scutum, 
  

   scutellum, 
  and 
  post-notum 
  brownish-yellow. 
  Pleurae 
  uniform 
  dull 
  

   yellow, 
  with 
  no 
  decided 
  contrasts 
  in 
  coloration. 
  Halteres 
  brownish- 
  

   yellow, 
  the 
  knob, 
  basally, 
  slightly 
  darker. 
  Legs: 
  coxae, 
  trochanters, 
  

   femora, 
  and 
  tibiae 
  dull 
  yellow, 
  tarsi 
  rather 
  lighter 
  yellow. 
  

  

  Wing: 
  dull 
  yellowish-hyaline, 
  darkest 
  at 
  the 
  tip; 
  stigma 
  oval, 
  

   brown; 
  veins 
  brown, 
  C 
  and 
  Sc 
  more 
  yellowish. 
  Venation: 
  Sc 
  veiy 
  

   long, 
  as 
  in 
  the 
  genus; 
  Scj 
  retracted 
  rather 
  far 
  backward, 
  so 
  that 
  Sci 
  

   is 
  rather 
  longer 
  than 
  Rj. 
  R 
  long, 
  cross 
  vein 
  r 
  just 
  before 
  its 
  tip, 
  

   oblique. 
  Rs 
  rather 
  long, 
  gently 
  arcuated, 
  about 
  equal 
  to 
  R2+3, 
  R2 
  

   short, 
  rather 
  sinuated. 
  R4+5 
  fused 
  with 
  M1+2, 
  obliterating 
  the 
  cross 
  

   vein 
  r-m, 
  this 
  fusion 
  continuing 
  for 
  a 
  short 
  distance 
  beyond 
  the 
  cross 
  

   vein 
  m, 
  when 
  the 
  veins 
  separate 
  in 
  a 
  symmetrical 
  fork. 
  M 
  in 
  a 
  line 
  

   with 
  M3 
  and 
  Cuj 
  ; 
  basal 
  deflection 
  of 
  M1+2 
  very 
  long, 
  longer 
  than 
  R,. 
  

   Cuj 
  about 
  equal 
  to 
  Cuj 
  ; 
  Cuj 
  fuses 
  with 
  M 
  just 
  before 
  the 
  fork 
  of 
  M 
  ; 
  at 
  

   the 
  lower 
  distal 
  angle 
  of 
  cell 
  first 
  Mj 
  the 
  veins 
  separate, 
  Cui 
  continuing 
  

   in 
  a 
  straight 
  line 
  with 
  Cui 
  + 
  Mg, 
  M3 
  arcuates 
  cephalad 
  to 
  the 
  cross 
  

   vein 
  m 
  and 
  continues 
  thence 
  straight 
  to 
  the 
  wing 
  margin. 
  Cuj 
  

   strongly 
  divergent 
  from 
  Cui, 
  forming 
  an 
  angle 
  of 
  about 
  75°. 
  Cuj 
  

   and 
  first 
  A 
  free 
  at 
  the 
  tip; 
  second 
  anal 
  rather 
  long. 
  (See 
  fig. 
  22.) 
  

  

  Abdomen: 
  tergum 
  dark 
  brown; 
  sternum, 
  segments 
  1-6 
  dull 
  yellow, 
  

   7-8 
  dark 
  brown; 
  genital 
  segment 
  dull 
  yellow; 
  valves 
  of 
  the 
  ovipositor 
  

   not 
  very 
  elongate, 
  dark 
  brown, 
  extreme 
  tips 
  paler, 
  3^ello^vish. 
  

  

  » 
  WllUston, 
  Trans. 
  Ent. 
  Soc. 
  Lond., 
  1896, 
  p. 
  293. 
  

   a 
  Idem, 
  p. 
  293, 
  pi. 
  101, 
  fig. 
  67. 
  

  

  