﻿310 
  

  

  S. 
  A. 
  NEAVE. 
  

  

  Tabanus 
  biguttatus, 
  Wied. 
  

  

  This 
  species 
  is 
  not 
  very 
  common 
  in 
  the 
  vicinity 
  of 
  Mt. 
  Mlanje, 
  where 
  the 
  

   conditions 
  are 
  not 
  specially 
  suitable, 
  as 
  it 
  prefers 
  lower 
  and 
  drier 
  country 
  with 
  

   sandy 
  river 
  beds. 
  The 
  capture 
  of 
  large 
  numbers 
  of 
  the 
  larvae 
  in 
  the 
  Shire 
  valley 
  

   has 
  already 
  been 
  recorded. 
  Many 
  others 
  were 
  subsequently 
  found 
  in 
  the 
  Ruo 
  

   valley 
  in 
  November. 
  The 
  grey 
  and 
  fulvous 
  forms 
  of 
  the 
  female 
  occur 
  in 
  about 
  equal 
  

   numbers 
  in 
  this 
  part 
  of 
  Nyasaland. 
  

  

  Fig. 
  20. 
  Tabanus 
  biguttatus, 
  Wied. 
  ; 
  pupal 
  aster 
  (a) 
  £, 
  and 
  (b) 
  $, 
  X 
  35 
  ; 
  dorso- 
  

   lateral 
  comb 
  of 
  (a) 
  $, 
  and 
  (b) 
  $, 
  X 
  50. 
  

  

  The 
  larva 
  is 
  of 
  a 
  type 
  which 
  has 
  many 
  representatives, 
  being 
  of 
  a 
  clear 
  white 
  

   colour, 
  except 
  in 
  individuals 
  about 
  to 
  pupate, 
  with 
  well-defined 
  pigmented 
  bands 
  

   and 
  spots 
  between 
  the 
  segments 
  and 
  on 
  the 
  anal 
  segment 
  (PL 
  xxvii, 
  fig. 
  8). 
  

   Several 
  species 
  have 
  larvae 
  of 
  this 
  type, 
  only 
  varying 
  in 
  the 
  amount 
  of 
  pigment 
  

   and 
  in 
  the 
  distribution 
  of 
  it 
  on 
  the 
  anal 
  segment. 
  

  

  The 
  pupal 
  aster 
  is 
  of 
  the 
  regular 
  type 
  and 
  the 
  dorso-lateral 
  combs 
  bear 
  long 
  

   spines, 
  which 
  are, 
  however, 
  shorter 
  and 
  stouter 
  (especially 
  in 
  the 
  $) 
  than 
  those 
  

   of 
  T. 
  corax. 
  

  

  Tabanus 
  ?secedens, 
  Walk. 
  

  

  One 
  female 
  was 
  taken 
  in 
  November 
  1912, 
  and 
  one 
  male 
  and 
  three 
  females 
  in 
  

   November 
  1913, 
  of 
  what 
  appears 
  to 
  be 
  a 
  form 
  of 
  or 
  perhaps 
  a 
  distinct 
  species 
  allied 
  

  

  