﻿330 
  

  

  W. 
  MANSFIELD-ADERS. 
  

  

  Anopheles 
  costalis, 
  Lw. 
  

  

  This 
  is 
  the 
  commonest 
  Anopheline 
  larva. 
  It 
  is 
  generally 
  found 
  in 
  small 
  collections 
  

   of 
  rain-water, 
  such 
  as 
  road-side 
  puddles, 
  borrow-pits, 
  water-holes 
  (dug 
  by 
  the 
  natives 
  

   for 
  storing 
  water), 
  shallow 
  swamps 
  surrounded 
  by 
  grass, 
  occasionally 
  in 
  cement 
  

   tanks, 
  oftener 
  in 
  those 
  with 
  algid 
  growth 
  attached 
  to 
  their 
  sides, 
  at 
  times 
  in 
  rain- 
  

   water 
  collected 
  in 
  dug-out 
  canoes 
  and 
  boats. 
  The 
  larvae 
  of 
  this 
  species 
  vary 
  greatly 
  

   in 
  colour, 
  some 
  being 
  quite 
  light, 
  some 
  dark, 
  others 
  almost 
  green, 
  the 
  variations 
  

   Leing 
  caused 
  by 
  the 
  type 
  of 
  food 
  ingested. 
  

  

  The 
  larva 
  has 
  a 
  small 
  head, 
  the 
  hairs 
  on 
  the 
  first 
  three 
  segments 
  of 
  the 
  abdomen 
  

   are 
  not 
  markedly 
  feathered 
  and 
  the 
  palmate 
  hairs 
  from 
  the 
  second 
  to 
  the 
  seventh 
  

   segment 
  are 
  not 
  very 
  conspicuous. 
  

  

  Anopheles 
  funestus, 
  Giles. 
  

  

  These 
  larvae 
  are 
  generally 
  found 
  in 
  backwaters 
  of 
  streams 
  and 
  at 
  the 
  edge 
  of 
  the 
  

   sluggish 
  rivers 
  where 
  the 
  water 
  is 
  overhung 
  by 
  grass 
  or 
  other 
  vegetation. 
  

   Occasionally 
  they 
  are 
  found 
  in 
  association 
  with 
  A. 
  costalis 
  in 
  the 
  Zanzibar 
  

  

  Fig 
  1. 
  Thorax 
  of 
  larvae 
  of 
  Anopheles 
  funestus, 
  Giles 
  (4tk 
  instar) 
  

  

  plumose 
  hairs, 
  greatly 
  enlarged. 
  

  

  a, 
  one 
  of 
  the 
  

  

  Protectorate. 
  The 
  larvae 
  are 
  small 
  and 
  black 
  in 
  colour 
  and 
  much 
  more 
  heavily 
  

   plumed 
  than 
  those 
  of 
  A. 
  costalis. 
  With 
  a 
  pocket 
  lens 
  a 
  pair 
  of 
  thick 
  feathered 
  hairs 
  

  

  