﻿CONTRIBUTION 
  TO 
  KNOWLEDGE 
  OF 
  TABANIDAE 
  OF 
  PALESTINE. 
  309 
  

  

  upper 
  (median) 
  frontal 
  callus, 
  instead 
  of 
  the 
  ill-defined 
  transverse 
  band, 
  which 
  

   represents 
  it 
  in 
  the 
  case 
  of 
  T. 
  pulverifer 
  ; 
  by 
  the 
  distal 
  segment 
  of 
  the 
  palpi 
  in 
  both 
  

   sexes 
  being 
  narrower 
  (less 
  sharply 
  pointed 
  in 
  the 
  $) 
  and 
  deeper 
  in 
  tint, 
  and 
  in 
  the 
  

   case 
  of 
  the 
  $ 
  bearing 
  many 
  black 
  hairs 
  on 
  the 
  outer 
  surface 
  ; 
  by 
  the 
  first 
  joint 
  

   of 
  the 
  antennae 
  in 
  both 
  sexes 
  being 
  smaller, 
  and 
  the 
  third 
  joint 
  paler, 
  narrower, 
  

   and 
  much 
  more 
  elongate 
  ; 
  by 
  the 
  wing-stigma 
  being 
  more 
  sharply 
  defined, 
  and 
  

   by 
  there 
  being 
  no 
  trace 
  of 
  an 
  appendix 
  to 
  the 
  anterior 
  branch 
  of 
  the 
  third 
  vein. 
  

   Tabanus 
  arenivagus 
  likewise 
  resembles 
  an 
  undetermined 
  species 
  represented 
  

   in 
  the 
  British 
  Museum 
  collection 
  by 
  a 
  solitary 
  $ 
  from 
  Arabia 
  (Muscat), 
  but 
  is 
  

   distinguished 
  by 
  the 
  front 
  in 
  the 
  $ 
  being 
  more 
  distinctly 
  narrower 
  below 
  (the 
  

   inner 
  margins 
  of 
  the 
  eyes 
  being 
  convergent) 
  ; 
  by 
  the 
  upper 
  portion 
  of 
  the 
  sub- 
  

   callus 
  in 
  the 
  ? 
  being 
  shining, 
  and 
  the 
  lower 
  frontal 
  callus 
  much 
  smaller, 
  and 
  not 
  

   reaching 
  the 
  inner 
  angles 
  of 
  the 
  eyes 
  ; 
  by 
  the 
  smaller 
  size 
  (less 
  prominent 
  upper 
  

   angle) 
  of 
  the 
  first 
  joint 
  of 
  the 
  antennae 
  ; 
  by 
  the 
  dorsum 
  of 
  the 
  abdomen 
  having 
  a 
  

   longitudinal 
  series 
  of 
  pale 
  triangles 
  in 
  the 
  median 
  fine, 
  instead 
  of 
  a 
  broad, 
  pale, 
  

   longitudinal 
  stripe 
  of 
  more 
  or 
  less 
  uniform 
  width 
  ; 
  and 
  by 
  the 
  stigma 
  of 
  the 
  wing 
  

   being 
  more 
  distinctly 
  marked. 
  

  

  13. 
  Tabanus 
  accensus, 
  sp. 
  n. 
  (figs. 
  11. 
  12). 
  

  

  $. 
  — 
  Length 
  (3 
  specimens) 
  12 
  to 
  13 
  '4 
  mm. 
  ; 
  width 
  of 
  head 
  3*8 
  to 
  4*25 
  mm. 
  ; 
  

   width 
  of 
  front 
  at 
  vertex 
  just 
  under 
  0*6 
  to 
  0'6 
  mm. 
  ; 
  length 
  of 
  wing 
  9 
  to 
  9*75 
  mm. 
  

  

  Small, 
  greyish 
  species, 
  with 
  two 
  frontal 
  colli 
  in 
  $ 
  ; 
  bare 
  eyes 
  ; 
  dorsum 
  of 
  thorax 
  

   neutral 
  grey 
  or 
  deep 
  neutral 
  grey, 
  longitudinally 
  striped 
  with 
  pale 
  olive-grey 
  ; 
  some- 
  

   what 
  narrow 
  straight-sided 
  abdomen, 
  smoke-grey 
  or 
  pale 
  pinkish 
  buff 
  above, 
  with 
  four 
  

   longitudinal 
  series 
  of 
  elongate 
  blackish 
  brown 
  marks, 
  lateral 
  borders 
  of 
  segments 
  pale 
  

   smoke-grey 
  pollinose, 
  hind 
  borders 
  of 
  second 
  and 
  following 
  segments 
  cream-buff 
  \ 
  

   and 
  parti- 
  coloured 
  legs. 
  

  

  Head 
  : 
  front 
  in 
  $ 
  smoke-grey 
  pollinose, 
  subcallus 
  pale 
  pinkish-buff 
  pollinose, 
  

   front 
  clothed 
  with 
  short, 
  pale 
  yellowish 
  or 
  bright 
  ochreous 
  appressed 
  hair, 
  in 
  region 
  

   of 
  vertex 
  sometimes 
  also 
  with 
  short 
  blackish 
  or 
  dusky 
  hair, 
  no 
  trace 
  of 
  an 
  ocellar 
  

   tubercle 
  but 
  a 
  tiny, 
  dusky, 
  mouse 
  grey 
  or 
  deep 
  mouse 
  grey 
  spot 
  in 
  middle 
  line 
  in 
  

   region 
  of 
  vertex 
  ; 
  face 
  and 
  jowls 
  greyish 
  white 
  pollinose, 
  clothed 
  with 
  whitish 
  

   hair 
  ; 
  occiput 
  pale 
  smoke-grey 
  pollinose, 
  hind 
  margin 
  fringed 
  above 
  with 
  very 
  

   short 
  and 
  inconspicuous 
  whitish 
  or 
  yellowish 
  white 
  hair 
  ; 
  front 
  in 
  $ 
  of 
  moderate 
  

   breadth 
  or 
  relatively 
  somewhat 
  broad, 
  slightly 
  but 
  distinctly 
  narrower 
  below, 
  about 
  

   four 
  times 
  as 
  long 
  as 
  its 
  breadth 
  at 
  the 
  lower 
  end 
  ; 
  lower 
  frontal 
  callus 
  shining 
  

   blackish 
  brown, 
  large, 
  quadrate 
  and 
  nearly 
  square, 
  extending 
  from 
  eye 
  to 
  eye 
  or 
  

   separated 
  from 
  eye 
  on 
  each 
  side 
  by 
  narrowest 
  possible 
  pollinose 
  interval, 
  lower 
  

   margin 
  convex 
  and 
  descending 
  slightly 
  below 
  level 
  of 
  inner 
  angles 
  of 
  eyes, 
  upper 
  

   edge 
  with 
  two 
  small 
  emarginations 
  and 
  consequently 
  produced 
  into 
  three 
  points, 
  

   upper 
  frontal 
  callus 
  black 
  or 
  blackish 
  brown, 
  oval 
  or 
  elliptical 
  oval, 
  not 
  connected 
  

   with 
  lower 
  ; 
  eyes 
  of 
  $ 
  in 
  life 
  with 
  upper 
  angles 
  and 
  lower 
  borders 
  dark 
  purplish 
  

   brown, 
  and 
  central 
  portion 
  metallic 
  bronze 
  or 
  bronze-green, 
  crossed 
  by 
  two 
  narrow, 
  

   deep 
  blue, 
  horizontal 
  bands 
  ; 
  palpi 
  ivory- 
  yellow 
  or 
  cream-coloured, 
  proximal 
  

   segment 
  clothed 
  with 
  long 
  whitish 
  hair, 
  distal 
  segment 
  in 
  $ 
  acuminate, 
  moderately 
  

   or 
  considerably 
  swollen 
  at 
  base, 
  clothed 
  on 
  outer 
  side 
  with 
  minute, 
  appressed, 
  

   (637) 
  g2 
  

  

  