﻿THE 
  EARLY 
  STAGES 
  OF 
  WEST 
  AFRICAN 
  MOSQUITOS. 
  

  

  419 
  

  

  on 
  segment 
  vii 
  only 
  small 
  delicate 
  hairs 
  are 
  present 
  ; 
  and 
  on 
  segment 
  viii 
  are 
  a 
  well 
  

   developed 
  tuft 
  (the 
  subsi 
  phonal 
  tuft) 
  ventral 
  to 
  the 
  siphon, 
  composed 
  of 
  3 
  to 
  7 
  sub- 
  

   plumose 
  hairs, 
  two 
  very 
  small 
  tufts 
  dorsally, 
  at 
  the 
  base 
  of 
  the 
  siphon, 
  and 
  a 
  very 
  

   small 
  delicate 
  tuft 
  at 
  the 
  base 
  of 
  the 
  anal 
  segment. 
  Comb 
  (fig. 
  8) 
  composed 
  of 
  about 
  

   thirty 
  (19 
  to 
  33) 
  spines 
  arranged 
  in 
  an 
  irregularly 
  triangular 
  patch 
  ; 
  each 
  spine 
  is 
  

   highly 
  chitinised, 
  with 
  several 
  sharply 
  pointed 
  teeth, 
  one 
  of 
  which 
  is 
  usuall}' 
  some- 
  

   what 
  longer 
  and 
  larger 
  than 
  the 
  others. 
  Siphon 
  (fig. 
  8) 
  well 
  chitinised, 
  dark 
  brown, 
  

   short, 
  and 
  forming 
  with 
  the 
  eighth 
  segment 
  an 
  angle 
  extremely 
  obtuse 
  anteriorly 
  ; 
  

   ratio 
  of 
  length 
  to 
  basal 
  breadth 
  about 
  2 
  to 
  1 
  . 
  Pecten 
  composed 
  of 
  1 
  to 
  4 
  dark 
  brown 
  

   barbed 
  spines. 
  Tuft 
  on 
  the 
  siphon 
  small, 
  situated 
  a 
  little 
  proximal 
  to 
  the 
  middle, 
  

   composed 
  of 
  two 
  or 
  three 
  subplumose 
  hairs. 
  Anal 
  segment 
  short, 
  with 
  a 
  small 
  

   dorsal 
  saddle-shaped 
  chitinous 
  plate. 
  Posterior 
  dorsal 
  setae 
  about 
  as 
  long 
  as 
  the 
  anal 
  

   papillae, 
  strong, 
  subplumose, 
  usually 
  single 
  or 
  double 
  above 
  and 
  below 
  on 
  each 
  side. 
  

   Lateral 
  seta 
  small, 
  a 
  delicate 
  tuft 
  of 
  hairs. 
  Subventrally 
  on 
  each 
  side 
  at 
  the 
  posterior 
  

   end 
  of 
  the 
  anal 
  segment 
  is 
  a 
  row 
  of 
  four 
  strong 
  graded 
  subplumose 
  setae 
  arising 
  

   from 
  a 
  common 
  chitinised 
  plate. 
  Anal 
  papillae 
  subequal, 
  long 
  and 
  broad, 
  tapering 
  

   slightty 
  at 
  their 
  ends 
  ; 
  nearly 
  twice 
  the 
  length 
  of 
  the 
  siphon 
  and 
  more 
  than 
  twice 
  

   that 
  of 
  the 
  anal 
  segment. 
  The 
  anal 
  papillae 
  are 
  very 
  frequently 
  missing. 
  

  

  Fig. 
  8. 
  Larva 
  of 
  Erctmopodites 
  chrysogaster, 
  Graham, 
  terminal 
  segments. 
  

  

  Pupa. 
  — 
  Edwards 
  (loc. 
  cit.) 
  has 
  also 
  figured 
  the 
  pupa, 
  but 
  the 
  remarks 
  made 
  when 
  

   dealing 
  with 
  the 
  larva 
  apply 
  also 
  to 
  this 
  figure. 
  Bacot 
  has 
  figured 
  the 
  paddles 
  and 
  

   the 
  terminal 
  segments 
  only. 
  A 
  fuller 
  description 
  of 
  the 
  pupa 
  will 
  therefore 
  be 
  given. 
  

  

  Length, 
  when 
  fully 
  extended, 
  7 
  mm. 
  to 
  8-5 
  mm. 
  The 
  pupa 
  is 
  well 
  chitinised, 
  

   and 
  its 
  general 
  form 
  is 
  well 
  shown 
  in 
  Edward's 
  figure. 
  

  

  Ccphalothorax 
  well 
  chitinised. 
  Wing-cases 
  rather 
  looseh' 
  attached 
  to 
  the 
  sides. 
  

   Respiratory 
  trumpets 
  (fig. 
  9 
  a) 
  shaped 
  like 
  the 
  corolla 
  of 
  a 
  foxglove, 
  opening 
  not 
  very 
  

   wide 
  ; 
  length 
  about 
  0-7 
  mm., 
  ratio 
  of 
  length 
  of 
  the 
  closed 
  portion 
  (meatus) 
  to 
  total 
  

   length 
  about 
  1 
  to 
  1-4. 
  Cephalothoracic 
  setae 
  arranged 
  much 
  as 
  in 
  Aedes 
  argenteus 
  

   [Stcgomyia 
  fasciata). 
  Post-ocular 
  and 
  antero-thoracic 
  setae 
  very 
  small 
  and 
  incon- 
  

   spicuous. 
  Dorsal 
  setae 
  long, 
  strong, 
  single 
  ; 
  slightly 
  subplumose 
  and 
  often 
  divided 
  

  

  