﻿136 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM 
  ^°^- 
  "^ 
  

  

  of 
  other 
  specimens 
  examined 
  I 
  am 
  deeply 
  grateful 
  to 
  Paul 
  Freeman, 
  

   of 
  the 
  British 
  Museum 
  (Natural 
  History), 
  to 
  Henry 
  Dietrich, 
  of 
  

   Cornell 
  University, 
  and 
  to 
  John 
  Lane, 
  of 
  the 
  University 
  of 
  Sao 
  Paulo. 
  

   For 
  the 
  generous 
  gift 
  or 
  loan 
  of 
  still 
  other 
  specimens 
  I 
  wish 
  to 
  thank 
  

   Mrs. 
  Elisabeth 
  C. 
  Beck 
  and 
  J. 
  A, 
  Mulrennan 
  of 
  Jacksonville, 
  Florida, 
  

   Bernard 
  Brookman 
  of 
  San 
  Francisco, 
  California, 
  Jean 
  A. 
  Laffoon 
  of 
  

   Ames, 
  Iowa, 
  and 
  Henry 
  K. 
  Townes 
  of 
  Raleigh, 
  North 
  Carolina. 
  

   The 
  figures 
  of 
  the 
  wings 
  and 
  legs 
  were 
  made 
  with 
  the 
  aid 
  of 
  a 
  micro- 
  

   projector 
  and 
  those 
  of 
  the 
  male 
  genitalia 
  with 
  the 
  aid 
  of 
  an 
  ocular 
  

   reticule 
  disc 
  and 
  squared 
  paper. 
  No 
  consistent 
  scale 
  was 
  used. 
  

  

  Family 
  Heleidae 
  

  

  Genus 
  Monohelea 
  Kieffer, 
  1917 
  

  

  Diagnosis. 
  — 
  Body 
  short, 
  not 
  very 
  haiiy. 
  Eyes 
  bare. 
  Mesonotal 
  

   pits 
  present 
  but 
  small. 
  Forelegs 
  and 
  midlegs 
  umnodified; 
  fourth 
  

   tarsal 
  segments 
  cylindrical 
  and 
  claws 
  small 
  and 
  equal 
  in 
  both 
  sexes; 
  

   hind 
  leg 
  with 
  femur 
  and 
  tibia 
  more 
  or 
  less 
  thickened, 
  but 
  without 
  

   spines, 
  basitarsus 
  with 
  a 
  spine 
  at 
  tip, 
  fourth 
  segment 
  cylindrical, 
  fifth 
  

   segment 
  in 
  female 
  with 
  one 
  very 
  long 
  claw, 
  the 
  other 
  absent 
  or 
  very 
  

   short, 
  male 
  claws 
  small 
  and 
  equal 
  except 
  hind 
  claw 
  as 
  in 
  female 
  in 
  

   tessellata 
  group; 
  empodium 
  absent. 
  Wings 
  with 
  fine 
  micro 
  trichiae, 
  a 
  

   few 
  macrotrichiae 
  at 
  wing 
  tip 
  ; 
  costa 
  extending 
  well 
  beyond 
  middle 
  of 
  

   wing; 
  two 
  radial 
  cells, 
  second 
  longer 
  than 
  first; 
  intercalary 
  fork 
  fairly 
  

   distinct; 
  crossvein 
  r-m 
  vertical; 
  median 
  fork 
  with 
  short 
  stem, 
  M2 
  

   sometimes 
  interrupted 
  at 
  base; 
  anal 
  vein 
  thickened 
  in 
  middle, 
  but 
  

   without 
  fold 
  at 
  thickening. 
  Male 
  genitalia 
  with 
  ninth 
  tergite 
  tapered, 
  

   the 
  caudal 
  margin 
  truncate 
  or 
  broadly 
  bilobed; 
  aedeagus 
  usually 
  with 
  

   a 
  pair 
  of 
  sharp-pointed, 
  tapered, 
  lateral 
  sclerites 
  and 
  an 
  accessory, 
  

   dorsomedian, 
  posterior 
  lobe; 
  parameres 
  consisting 
  of 
  paired, 
  sub- 
  

   median 
  sclerites 
  of 
  irregular 
  shapes. 
  

  

  Key 
  to 
  the 
  American 
  species 
  of 
  Monohelea 
  

  

  1. 
  Wings 
  without 
  markings; 
  mesonotum 
  shining 
  black 
  (subgenus 
  Schizohelea) 
  . 
  

  

  1. 
  leucopeza 
  (Meigen) 
  

   Wings 
  with 
  pronounced 
  dark 
  markings; 
  mesonotum 
  pruinose, 
  often 
  with 
  mark- 
  

   ings 
  (subgenus 
  Monohelea) 
  2 
  

  

  2. 
  Hind 
  femur 
  and 
  tibia 
  yellow, 
  with 
  dark 
  brown 
  rings 
  {hieroglyphica 
  group) 
  . 
  3 
  

   Hind 
  femur 
  and 
  tibia 
  shining 
  black, 
  only 
  knee 
  spot 
  yellow 
  9 
  

  

  3. 
  Forelegs 
  and 
  midlegs 
  with 
  distinct 
  dark 
  brown 
  bands; 
  wings 
  often 
  with 
  exten- 
  

  

  sive 
  macrotrichiae 
  4 
  

  

  Forelegs 
  and 
  midlegs 
  yellowish, 
  without 
  distinct 
  bands; 
  wings 
  with 
  macro- 
  

   trichiae 
  only 
  at 
  extreme 
  distal 
  margin 
  6 
  

  

  4. 
  Wings 
  with 
  macrotrichiae 
  over 
  distal 
  third; 
  wing 
  markings 
  extensive 
  5 
  

  

  Wing 
  without 
  apparent 
  macrotrichiae; 
  wing 
  markings 
  reduced, 
  X-shaped 
  

  

  marking 
  in 
  cells 
  Mi 
  and 
  M2 
  broken 
  up 
  into 
  3 
  discrete 
  spots. 
  

  

  6. 
  texana, 
  new 
  species 
  

  

  