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  STANLEY 
  HIRST. 
  — 
  ON 
  THE 
  PARASITIC 
  ACARI 
  

  

  Deutonymph. 
  Dorsal 
  shields 
  both 
  closely 
  resembling 
  those 
  of 
  the 
  female. 
  Two 
  

   or 
  three 
  platelets 
  are 
  situated 
  on 
  each 
  side 
  of 
  the 
  anterior 
  shield. 
  A 
  small 
  but 
  distinct 
  

   platelet 
  is 
  placed 
  above 
  the 
  interval 
  between 
  the 
  first 
  and 
  second 
  legs 
  and 
  it 
  is 
  narrow 
  

   and 
  elongated 
  instead 
  of 
  being 
  oval 
  as 
  in 
  the 
  deutonymph 
  of 
  D. 
  muris. 
  Sternal 
  plate 
  

   projecting 
  backwards 
  distinctly 
  beyond 
  the 
  last 
  coxae 
  ; 
  three 
  pairs 
  of 
  hairs 
  are 
  

   present 
  on 
  it. 
  Peritreme 
  rather 
  short, 
  and 
  apparently 
  not 
  reaching 
  as 
  far 
  as 
  the 
  

   middle 
  of 
  the 
  second 
  coxa. 
  Length 
  of 
  body, 
  1*1 
  mm. 
  

  

  Fig. 
  10. 
  Ventral 
  view 
  of 
  deutonymph 
  of 
  Dermanyssus 
  aegyptius, 
  Hirst. 
  

  

  Protonymph. 
  Dorsal 
  shields 
  very 
  like 
  those 
  of 
  the 
  adult 
  and 
  deutonymph 
  ; 
  the 
  

   posterior 
  tail-like 
  prolongation 
  of 
  the 
  main 
  shield 
  is 
  much 
  narrower 
  than 
  is 
  the 
  case 
  

   in 
  the 
  protonymphs 
  of 
  D. 
  muris 
  and 
  D. 
  sanguineus 
  ; 
  four 
  minute 
  platelets 
  are 
  

   situated 
  on 
  each 
  side 
  of 
  this 
  part 
  of 
  the 
  shield, 
  those 
  of 
  the 
  two 
  anterior 
  pairs 
  being 
  

   elongated, 
  but 
  the 
  posterior 
  ones 
  are 
  oval 
  and 
  they 
  are 
  very 
  minute 
  and 
  incon- 
  

   spicuous. 
  There 
  are 
  two 
  little 
  platelets 
  on 
  the 
  side 
  of 
  the 
  body 
  ; 
  the 
  anterior 
  one 
  

   is 
  situated 
  as 
  in 
  the 
  deutonymph, 
  and 
  the 
  other 
  is 
  in 
  front 
  of 
  the 
  anterior 
  end 
  of 
  

   the 
  peritreme. 
  Sternal 
  plate 
  extending 
  backwards 
  beyond 
  the 
  middle 
  of 
  the 
  last 
  

  

  